Specialist Group on Use of Macrophytes in Water Pollution ... - IWA

<strong>Specialist</strong> <strong>Group</strong> on 

Use of Macrophytes in Water Pollution Control 

Newsletter No. 35 

November 2009 

Edited by: Dr Suwasa Kantawanichkul 

Department of Environmental Engineering 

Faculty of Engineering 

Chiang Mai University 

Chiang Mai 

50200 

Thailand 

Email: suwasa@eng.cmu.ac.th 

<strong>Group</strong> organisation 

Chair: Dr Jan Vymazal (vymazal@yahoo.com) 

Secretary: Dr Suwasa Kantawanichkul (suwasa@eng.cmu.ac.th) 

Regional Coordinators 

ASIA: Dr Zhai Jun (zhaijun99@126.com; zhaijun@cqu.edu.cn) 

SOUTHEAST ASIA: Dr Suwasa Kantwanichkul (suwasa@eng.cmu.ac.th) 

AUSTRALIA: Dr Margaret Greenway (m.greenway@mailbox.gu.edu.au) 

NEW ZEALAND: Dr Chris C Tanner (c.tanner@niwa.co.nz) 

EUROPE: Dr Jan Vymazal (vymazal@yahoo.com) 

Professor Reimund Harberl (raimund.haberl@boku.ac.at) 

Dr Guenter Langergraber (guenter.langergraber@boku.ac.at) 

Professor Brian Shutes (b.shutes@mdx.ac.uk) 

Dr Fabio Masi (masi@iridra.com) 

Mr Heibert Rustige (rustige@akut-umwelt.de) 

MIDDLE EAST: Professor Michal Green (agmgreen@tx.technion.ac.il) 

NORTH AMERICA: Dr Otto Stein (ottos@ce.montana.edu) 

SOUTH AMERICA: Dr Gabriela Dotro (gdotro@gmail.com) 

____________________________________________________________________________________________________ 

IWA <strong>Specialist</strong> <strong>Group</strong> on Use of Macrophytes in Water Pollution Control: Newsletter No. 35 1

CONTENTS 

Preface by the Secretary.............................................................................................................. 3 

First call for the 2010 conference in Venice ............................................................................... 4 

3rd International Symposium on Wetland Pollutant Dynamics and Control – WETPOL2009, 

20–24 September 2009, Barcelona, Spain ................................................................................ 10 

Unclogging the future of treatment wetlands ............................................................................ 11 

Application of constructed wetland for controlling leachate pollution from solid waste 

disposal ..................................................................................................................................... 15 

Estrogen removal in wetlands – review .................................................................................... 17 

Update on Constructed Wetland Applications in Italy ............................................................. 24 

The treatment wetland of the Montreal Biosphere: 15 years later ............................................ 35 

News from IWA Headquarters ................................................................................................ 40 

New from IWA Publishing ....................................................................................................... 42 

Disclaimer: This is not a journal, but a Newsletter issued by the IWA <strong>Specialist</strong> <strong>Group</strong> on Use of Macrophytes 

in Water Pollution Control. Statements made in this Newsletter do not necessarily represent the views of the 

<strong>Specialist</strong> <strong>Group</strong> or those of the IWA. The use of information supplied in the Newsletter is at the sole risk of the 

user, as the <strong>Specialist</strong> <strong>Group</strong> and the IWA do not accept any responsibility or liability. 

___________________________________________________________________________ 

2 IWA <strong>Specialist</strong> <strong>Group</strong> on Use of Macrophytes in Water Pollution Control: Newsletter No. 35

PREFACE BY THE SECRETARY 

Dear Members, 

Greetings and welcome to the 35th edition of our <strong>Specialist</strong> <strong>Group</strong> Newsletter! We are very 

pleased with the success of our <strong>Group</strong>‘s work, which is reflected in the attendance to 

specialists‘ conferences and contributions to this Newsletter, among others. In this edition, 

we have some important announcements that pertain to our <strong>Group</strong> activities: 

1) Newsletter frequency: Given the success of the continuous edition of the newsletter, and 

addressing a stated need for greater communication between the members of our <strong>Group</strong>, 

we are now aiming to release two issues of the newsletter per calendar year. The first 

edition of the 2010 newsletter is planned for April/May, with a second issue to be sent out 

in October/November. This should enable faster, up-to-date communications on topics 

relevant to our Members. 

2) Newsletter contributions: Directly related to the purpose of the newsletter and the 

increase in issuing frequency, we kindly request all members to submit short articles, 

news, or any other activities that might be of interest for our <strong>Specialist</strong> <strong>Group</strong> Members 

for their potential inclusion in the newsletter. These can be sent directly to the <strong>Group</strong> 

Secretary at: suwasa@eng.cmu.ac.th. Please note the deadline for the April/May issue 

will be March 15, 2010. 

3) Coordinators changes: Following up on the discussions held at the 11th International 

Conference on Wetland Systems for Water Pollution Control in November 2008, we have 

updated our Coordinators for the different geographical areas to facilitate the exchange of 

information among our Members. The Coordinators contribute to steering and balancing 

the article contributions from each region and are available for any region-specific 

questions you may have. They have been designated and grouped as follows: 

� Asia: Dr Zhai Jun (email:zhaijun99@126.com, zhaijun@cqu.edu.cn) 

� South East Asia: Suwasa Kantwanichkul (email: suwasa@eng.cmu.ac.th) 

� Australia: Margaret Greenway (email: m.greenway@mailbox.gu.edu.au) 

� New Zealand: Chris Tanner (email: c.tanner@niwa.co.nz) 

� Europe: 

o Jan Vymazal (email: vymazal@yahoo.com), 

o Reimund Harberl (email: raimund.haberl@boku.ac.at), 

o Guenter Langergraber (email: guenter.langergraber@boku.ac.at), 

o Brian Shutes (email: b.shutes@mdx.ac.uk), 

o Fabio Masi (email: masi@iridra.com), 

o Heibert Rustige (email: rustige@akut-umwelt.de) 

� Middle East: Michal Green (email: agmgreen@tx.technion.ac.il) 

� North America: Otto Stein (email: ottos@ce.montana.edu) 

� South America: Gabriela Dotro (email: gdotro@gmail.com) 

As always, we strive to have an active <strong>Group</strong> and provide true benefits to our Members. 

Therefore, if you have any suggestions for improvement or adding value to our current 

activities as a <strong>Group</strong>, please do not hesitate to send them as well. 

Looking forward to hearing from you. Best regards, 

Suwasa Kantawanickul 

____________________________________________________________________________________________________ 


FIRST CALL FOR THE 2010 CONFERENCE IN VENICE 

___________________________________________________________________________ 


____________________________________________________________________________________________________ 


___________________________________________________________________________ 


____________________________________________________________________________________________________ 


___________________________________________________________________________ 


____________________________________________________________________________________________________ 


3rd International Symposium on Wetland Pollutant Dynamics and Control – WETPOL2009, 

20–24 September 2009, Barcelona, Spain 

Guenter Langergraber 

Institute of Sanitary Engineering and Water Pollution Control, University of Natural 

Resources and Applied Life Sciences, Vienna (BOKU), Muthgasse 18, A-1190 Vienna, Austria 

(tel: +43-(0)1-47654-5814; fax: +43-(0)1-3689949; 

email: guenter.langergraber@boku.ac.at) 

Introduction 

The basic idea behind the WETPOL symposium series is to bring together scientist working 

on processes in natural and constructed wetlands. The very first WETPOL Symposium 

‗Wetland Pollutant Dynamics and Control‘ was held in September 2005 in Gent, Belgium. 

The second WETPOL Symposium took place in September 2007 in Tartu, Estonia. More 

than 200 delegates from more than 30 countries participated in this second symposium. 

WETPOL 2009 was held from 20 to 24 September 2009 in Barcelona, Spain. The symposium 

was organised by the Department of Hydraulics, Maritime and Environmental Engineering at 

the Technical University of Catalonia (UPC) and the Institute of Environmental Assessment 

and Water Research (IDAEA-CSIC) in Barcelona. 

Over 250 participants from 38 countries attended WETPOL 2009, in total 5 plenary and 5 

keynote lectures were presented to the full auditorium as well as 100 oral and 95 poster 

presentations in parallel session. The plenary lecturers were presented by Eloy Bécares 

(Spain), Yong Cai (USA), Peter Kuschk (Germany), Patrick J. Megonigal (USA), and Carlos 

Vale (Portugal). Topics of the parallel sessions included the wetland‘s role in pollutant 

management at catchment scale, pollutant modelling in wetlands, behaviour of priority and 

emerging pollutants in wetlands, molecular and microbial advances in wetlands, role of 

wetlands‘ plants in pollution control, trace elements, technological developments in 

constructed wetlands, etc. 

The follow-up event, WETPOL 2011, is planned to be held in conjunction with two other 

meetings, the Society of Wetland Scientists annual meeting and the Biogeochemistry Wetland 

Symposium in Prague, Czech Republic. More information will be available soon at the 

WETPOL website. 

References 

Bayona, J.M., García, J. (Eds.): 3rd International Symposium on ‗Wetland Pollutant 

Dynamics and Control – WETPOL 2009‘ – Book of Abstracts, 20–24 September 2009, 

Barcelona, Spain (ISBN-10: 978-84-692-5587-2, CD-ROM). 

WETPOL website: http://www.wetpol.org/ 

___________________________________________________________________________ 


UNCLOGGING THE FUTURE OF TREATMENT WETLANDS 

A <strong>Specialist</strong> Workshop on Treatment Wetland Clogging was recently hosted by Aston 

University, UK. The two-day event was free to attend and attracted experts from across 

academia, government and industry. The delegates, who hailed from Argentina, India, 

Germany Spain and the UK, were keen to address a problem which is often considered ‗the 

Achilles-heel‘ of Treatment Wetland technology. The aim of the seminar was to build on 

discussions held in Indore, India (at the 11th IWA International Conference on Wetland 

Systems for Water Pollution Control) where it was suggested that a focus of the next 

decade‘s research should be an improved understanding and viable solutions regarding the 

clogging phenomenon. Clogging manifests itself as a loss of subsurface media porosity (often 

gravels or sands) due to the physical, chemical and biological mechanisms of wastewater 

purification. One example is deposition of wastewater solids within the gravel pore spaces, 

due to settling and filtration. The result is a loss of hydraulic conductivity through the 

subsurface over time, leading to the development of preferential flow-paths and overland 

flow. The reduction in reactor volume will shorten the hydraulic residence time of the system, 

and in extreme cases can prevent the system from achieving the required treatment 

performance [1]. 

The first day of the workshop comprised a rich and varied collection of presentations 

delivered by the participants. Government agency the UK Coal Authority described their 

experience of clogging in wetlands for mine wastewater treatment. Water utility provider 

Severn Trent Water explained how the design of wetlands for municipal wastewater 

treatment has evolved based on their experiences of clogging [2], such as improved inlet 

distributors and coarser specifications for gravel substrates. Representatives from consulting 

wetland engineers such as ARM Ltd. and North American Wetland Engineering described 

novel initiatives to restore subsurface flow through systems that have become clogged, 

including in-situ gravel washing technologies [3] and application of chemical oxidants such 

as hydrogen peroxide [4]. Key note speaker Joan García from the Technical University of 

Catalonia, presented his research on how the composition of wastewater (particulate or 

dissolved, refractory or labile) can exacerbate the clogging problem [5]. Amongst others, 

contributions from academia included emerging methods to measure and characterise 

treatment wetland clogging in-situ [6, 7] (Aston University, UK and Technical University of 

Catalonia, Spain), how accumulation of specific metals such as chromium can limit the 

lifespan of industrial wastewater treatment wetlands [8] (National University of Litoral, 

Argentina), the way that computer models can be used to simulate the interaction between 

clogging and wetlands hydraulics, and how climatic conditions must be considered when 

deriving models for wetland hydrology [9, 10] (Aston University). 

On the second day, delegates visited four local sewage treatment plants operated by Severn 

Trent Water, where they saw demonstrations of the latest techniques for the measurement of 

clogging and the restoration of hydraulically mature wetlands. The event organisers from 

Aston University‘s Sustainable Environment Research <strong>Group</strong> stated, ―the event offered the 

perfect platform to discuss the wetland clogging issue, and the information exchanged laid 

the foundations for future research by summarising the state of current understanding within 

the field, and identifying gaps in the knowledge. This has prompted us all to consider new 

ways of tackling clogging, and will hopefully stimulate and shape the future of clogging 

research in wetland science.‖ Based on the conclusions of the workshop it was suggested that 

avenues for the next decade‘s clogging research should specifically address: 

____________________________________________________________________________________________________ 


� Characterisation and comparison of how different wetland system designs develop 

clogging. Ways of measuring the extent of clogging in these systems and guidelines 

for when to intervene (maintenance/refurbishment). 

� The effect of water depth on algal growth and surface blinding in systems with 

overland flow. The effect of water depth, gravel properties (particle shape, sphericity, 

and packing arrangement) and leaf litter contributions, on clogging. 

� Investigations into the mechanisms behind clogging including characterisation of 

accumulated matter and its ability to decompose depending on microbial dynamics 

and the different oxidation states found in wetland subsurfaces, the impact of airlocking 

on hydraulic conductivity as caused by methanogenesis, and the effect of 

temperature on rhizome growth and penetration. 

� Possible design improvements such as inlet distributors that achieve uniform width 

loading, improved flow depth regulators to prevent overland flow, buoyant media 

such as plastics as opposed to static media such as gravels. 

� Measurement of the hydraulic improvements offered by operational solutions such as 

using multiple beds with alternate loading/drying periods, when compared to 

continuous operation. 

� Cost versus improvement analysis of remediation strategies such as gravel washing 

and chemical oxidant application, over traditional refurbishment methods such as 

replacement of clogged media with fresh media. 

For more information regarding the workshop outcomes or clogging in treatment wetlands 

please contact p.a.davies@aston.ac.uk 

Delegates of the <strong>Specialist</strong> Workshop on Treatment Wetland Clogging, Aston University, 

UK, March 2009. Photo taken at Gaydon Sewage Treatment Work, Warwickshire, UK 

(Severn Trent Water), courtesy of Jaime Nivala. 

___________________________________________________________________________ 


Paul Knowles (Aston University) and Anna Pedescoll (Technical University of Catalonia), 

demonstrating the latest techniques for the in-situ measurement of wetland clogging. Photo 

taken at Moreton Morrell Sewage Treatment Works, Warwickshire UK (Severn Trent 

Water), courtesy of Jaime Nivala. 

____________________________________________________________________________________________________ 


References 

1. Kadlec, R.H. and S. Wallace, Treatment wetlands. 2008, Boca Raton, Fla.: CRC ; 

London : Taylor & Francis [distributor]. 1 v. 

2. Griffin, P., L. Wilson, and D. Cooper. Changes in the use, operation and design of subsurface 

flow constructed wetlands in a major UK water utility. in 11th International 

Conference on Wetland Systems for Water Pollution Control. 2008. Indore, India: 

Vikram University and IWA. 

3. http://www.armreedbeds.co.uk/Field_Services/refurbishment/. [cited 15/06/2009]. 

4. Nivala, J. and D.P.L. Rousseau, Reversing clogging in subsurface-flow constructed 

wetlands by hydrogen peroxide treatment: two case studies. Water Sci. Technol., 2009. 

59(10): p. 2037-2046. 

5. Caselles-Osorio, A. and J. García, Performance of experimental horizontal subsurface 

flow constructed wetlands fed with dissolved or particulate organic matter. Water 

Research, 2006. 40(19): p. 3603-3611. 

6. Knowles, P.R. and P.A. Davies, A method for the in-situ determination of the hydraulic 

conductivity of gravels as used in constructed wetlands for wastewater treatment. 

Desalination and Water Treatment, 2009: p. In Press. 

7. Pedescoll, A., et al., Practical method based on saturated hydraulic conductivity used to 

assess clogging in subsurface flow constructed wetlands. Ecological Engineering, 2009. 

In Press. 

8. Dotro, G.C., P. Palazolo, and D. Larsen, Chromium fate in constructed wetlands treating 

tannery wastewaters. Water Environment Research, 2009. In Press. 

9. Hedges, P.D., P.M. Fermor, and J. Dušek, The Hydrological Sustainability of 

Constructed Wetlands for Wastewater Treatment, in Wastewater Treatment, Plant 

Dynamics and Management in Constructed and Natural Wetlands, J. Vymazal, Editor. 

2008. p. 111-120. 

10. Knowles, P.R., P. Griffin, and P.A. Davies. A finite element approach to modelling the 

hydrological regime in horizontal subsurface flow constructed wetlands for wastewater 

treatment. in 7th International Workshop on Nutrient Cycling and Retention in Natural 

and Constructed Wetlands. 2009. Trebon, Czech Republic. 

___________________________________________________________________________ 


APPLICATION OF CONSTRUCTED WETLAND FOR CONTROLLING 

LEACHATE POLLUTION FROM SOLID WASTE DISPOSAL 

Chart Chiemchaisri 

Department of Environmental Engineering/National Center of Excellence for Environmental 

and Hazardous Waste Management, Faculty of Engineering, Kasetsart University, Bangkok 

10900, Thailand 

An investigation in Thailand is focusing on the application of constructed wetland for direct 

treatment of leachate at municipal solid waste disposal site. The main purpose of treatment 

was to reduce the organic concentration in leachate to an acceptable concentration so that it 

can be further utilize for irrigation on the landfill top soil. Two configurations of constructed 

wetland were tested, i.e. horizontal sub-surface flow (HSF, Figure 1) and vertical flow (VF) 

types. Cattail was used as the vegetation in both systems. They were applied for primary 

treatment of young leachate as well as post treatment for stabilized leachate. In each case, the 

hydraulic loading rate (HLR) is varied between 0.01-0.056 m 3 /m 2 .d, equivalent to hydraulic 

retention time (HRT) in range of 28 and 5 days. 

Pollutant removal efficiencies in constructed wetland 

Applied leachate had COD concentration of about 3,000-5,000 mg/l with BOD/COD ratio of 

0.6-0.7 and 0.05-0.1 for young and stabilized leachate respectively. In HSF and VF systems 

treating young leachate, high organic removal of more than 90% was achieved up to HLR of 

0.028 m 3 /m 2 .d. In stabilized leachate case, moderate organic removal efficiencies were 

achieved. TKN removal was higher in VF (60-70%) as compared to HSF system (40-50%). 

Temporal accumulation of oxidized nitrogen was observed at high nitrogen loading condition 

(from stabilized leachate) causing some death of plant (Figure 2). Moderate nitrogen removal 

efficiencies was achieved at HLR up to 28 m 3 /m 2 .d for stabilized leachate where influent 

TKN concentration was controlled at about 100-300 mgL -1 . 

Gravel 

Influent 

Coarse sand 

Figure 1 Schematic of HSF constructed wetland system 

____________________________________________________________________________________________________ 

IWA <strong>Specialist</strong> <strong>Group</strong> on Use of Macrophytes in Water Pollution Control: Newsletter No. 35 15 

3 m 

Effluent 

0.40 m 

0.8 m 

1.3 m

Figure 2 Plant condition in constructed wetland treating young leachate (left) and stabilized 

leachate (right). 

Greenhouse gas emission during the treatment 

Greenhouse gases emission from the HSF unit was measured by close-flux chamber method. 

The close flux chamber has 0.3 m diameter and 0.3 m height. The base of chamber was made 

of stainless steel with 0.3 m diameter and 0.125 m height. The gas sampling was regularly 

conducted during 2 hours after the installation of chamber during which gas concentration 

gradient in the chamber relates directly to the its emission rate. 

The emission of methane gas was ranged between ND level up to 0.71 g/m 2 .d. The maximum 

emission rate was found highest at inlet zone and reduced along the flow. The emission of 

greenhouse gas was also found varied seasonally. During rainy season, the emission was 

found lower as considerable amount of rain diluted the water in the system thus led to lower 

methane emission. Methane emission was comparable higher during summer under elevated 

temperature. 

Introduction of internal recirculation in the system also helped reducing greenhouse gas 

emission. 

More detailed information can be found in Chiemchaisri, C. et al., Leachate treatment and 

greenhouse gas emission in subsurface horizontal flow constructed wetland. Bioresour. 

Technol. (2009), doi:10.1016/j.biortech.2008.12.028. 

___________________________________________________________________________ 


ESTROGEN REMOVAL IN WETLANDS – REVIEW 

Dana Milstein a , Avital Gasith a and Dror Avisar b 

a Faculty of Life sciences, Department of Zoology, Tel Aviv University, Israel 

b Geography and Human Environment, Hydrochemistry Laboratory, Tel Aviv University, 

Israel 

One of the key environmental problems facing humanity emanates from the widespread and 

diverse contamination of freshwater (Schwarzenbach et al., 2006). New contaminants are 

continuously being identified and become the focus of new investigations. Recently, micropollutants 

were recognized as a threat to the integrity of aquatic environments 

(Schwarzenbach et al., 2006). These pollutants are compounds that are present in the 

environment in minute concentrations (micro and nanograms per liter) and thus are hard to 

detect. Known micro-pollutants include chemicals for human use such as pesticides, 

pharmaceuticals and cosmetic products. Such contaminants reach aquatic systems and soils 

together with the effluents and sludge that are discharged into the environment (Shore et al., 

1993; Ingerslev and Halling-Sørensen, 2003). The presence of estrogens in primary and 

secondary effluents reveals that they are not completely removed by conventional wastewater 

treatments (Kreuzinger et al., 2004; Pawlowski et al., 2004; Kolodziej et al., 2003). 

Developing and implementing cost-effective wastewater treatment technologies to remove 

micro-pollutants is therefore a major challenge (Schwarzenbach et al., 2006). Here we review 

the current knowledge on the removal efficiency of estrogens from municipal wastewater 

effluent by environmentally friendly, wetland technology. Findings of our recently completed 

research are included (Milstein et al., in preparation). 

Estrogens 

Estrogenic compounds are lipophilic; natural or synthetic molecules. Natural estrogens such 

as estrone (E1), 17�-estradiol (E2) and estriol (E3) are synthesized in the vertebrate body. 

Synthetic estrogens such as 17�- ethinylestradiol (EE2) and mestranol (MeEE2) are used as 

pharmaceuticals (e.g., contraceptives). There is evidence that at the low concentrations at 

which these compounds are present in the environment they interfere with normal endocrine 

activity (e.g., Tyler and Jobling, 2008). One of the earliest pieces of evidence for the 

biological effects of estrogenic compounds found in the environment was that of the increase 

of a precursor molecule for egg yolk synthesis (vitelogenin) in plasma of male fish (e.g. 

Lintelmann et al., 2003). In addition, inhibition of testicular growth and diminution of 

secondary sex characteristics of male fish were reported (Jobling et al., 1996; Jobling et al., 

2002). There is evidence that invertebrates too (e.g. molluscs and crustaceans) are affected by 

exposure to estrogenic pollution originating from vertebrates (Jobling et al., 2004; Gagne et 

al., 2003; Segner et al., 2003; Czech et al., 2001). 

Potential mechanisms for estrogen removal in wetlands 

Physical, chemical and biological processes attenuate organic compounds in wetlands (Imfeld 

et al., 2009). These processes involve evaporation, photo-chemical oxidation, sedimentation, 

sorption, and biological degradation mechanisms (e.g., Kadlec, 1992; Imfeld et al., 2009). 

Little is known on the relative contribution of each mechanism to the removal of organic 

compounds (Imfeld et al., 2009). Moreover, the relative importance of a particular process 

can be expected to vary, depending on system attributes such as wastewater quality, flow 

pattern (surface flow, sub-surface, horizontal or vertical flow), operational variables (e.g. 

____________________________________________________________________________________________________ 


flow regime, hydraulic retention time), soil matrix, vegetation type and density, and 

environmental conditions such as temperature, oxygen regime, and solar irradiation. 

Estrogens are relatively hydrophobic compounds (log Kow 2.81-4.67), thus one of the 

mechanisms by which they can be removed is sorption to hydrophobic surfaces (e.g., organic 

rich soils; White et al., 2006; Matamoros and Bayona, 2008). Similar to other organic 

compounds, estrogens are also exploited and degraded by microorganisms (e.g., Matamoros 

and Bayona, 2008; Imfeld et al., 2009). Another possible mechanism for estrogen breakdown 

is photo-degradation; however this is relevant only to surface flow wetlands, particularly 

shallow and clear ones (White et al., 2006). The low vapor pressure of estrogens makes 

evaporation a less probable mechanism for removing them in wetlands (Ingerslev and 

Halling-Sørensen, 2003). 

Evidence for estrogen removal in wetland systems 

Elimination of estrogenic compounds from wastewater is expressed either by decrease in 

concentration or by decline in estrogenic activity (estrogenicity). Here we present the data for 

different types of constructed wetlands, in order of increasing rate of attenuation. 

Surface flow wetlands (SF) 

Data on removal efficiency of estrogens or estrogenicity in surface-flow wetlands are 

conflicting. Some reports contend that there is no or little attenuation of estrogens, while 

others report measurable removal. Insignificant removal of estrogenic activity was 

demonstrated for example in the Prado wetland (Riverside, California; Xie et al., 2004) 

treating the water of the Santa Ana River that receives tertiary-treated effluent (Bachand and 

Horne, 2000). The river water was discharged into 50 shallow SF ponds (average depth 0.75 

to 0.92m) with average discharge of 3.6m 3 /s, and hydraulic retention time (HRT) of 6 days. 

No difference in esterogenicity (in vivo rainbow trout vitellogenin expression and in vitro 

yeast estrogen screening assays) was found between river water entering and leaving the 

Prado wetland. Persistence of estrogenic compounds (E2, E1; maximum concentration of 4 

and 12 ng/l, respectively) was also found in shallow interconnected engineered ponds 

receiving municipal secondary effluent with an HRT of 6-7 days (Kolodziej et al., 2003). In a 

study in Illinois, Peterson and Lanning (2009) reported the failure of an SF system (3 

consecutive cells, 6X15X1.2m, each with a variety of emergent and floating macrophytes), 

receiving secondary municipal effluent (ca. 11.4 m 3 /day; 4 days mean HRT), to significantly 

remove E2 and E1 (mean influent concentration 32.8-55.5 and 73.6-74.8 ng/l, respectively). 

The authors found only poor removal of E2 (13%) and failure to remove E1 in a similar 

surface flow system that had only floating aquatic plants (duckweed and algae). Difference in 

the removal of E2 by the above SF systems was attributed to different plant composition. We 

examined removal of E2 and E1 in an hybrid wetland in Israel where an SF pond (25m 2 , 

depth – 0.55m, a variety of emergent and submerged macrophytes; discharge 12m 3 /day; 

calculated HRT – ca 15 hrs) provided final treatment (Milstein et al., in preparation). We too 

found no significant removal of E2 (influent concentration of E2 2.7ng/l; E1 was below 

detection limit of

Prado wetland (Xie et al., 2004) by the relatively sparser vegetation in the latter. They 

suggest that the vegetation provides a surface area for biofilm development, on which 

biodegradation and sorption occur. In a study in north-central Texas, Hemming et al. (2001) 

reported removal of estrogenicity (vitellogenin expression) from municipal effluent flowing 

through an SF wetland. In that study wastewater effluent (activated sludge treatment) entered 

a 46X46m wetland separated into lanes. Lane depth varied from a few centimeters near the 

inflow to 0.6m at the outflow (average discharge rate ca. 3m 3 /h; average HRT of 4.3 days). 

The system contained a variety of emergent and floating macrophytes. The authors reported 

significantly lower levels of estergenicity (vitellogen in plasma of male fathead minnow - 

Pimephales promelas) in the wetland effluent relative to the influent. High removal 

efficiency of E2 and EE2 (75 and 89%, respectively) was reported in a study in an SF 

wetland in California treating secondary effluent (Huang and Sedlak, 2001). No details of 

wetland attributes were given. The authors attribute estrogen attenuation to "physical and 

biological processes". 

Horizontal sub-surface flow wetlands (HSSF) 

We found no significant attenuation of E2 (influent concentration 2.1 ng/l) in a plant-free, 

HSSF cell (area - ca. 30m 2 , depth – 0.55m, discharge 12m 3 /day; calculated HRT – ca. 16 hrs; 

Milstein et al., in preparation). Peterson and Lanning (2009) reported 27% attenuation of E2 

and failure of removal of E1 in an HSSF with a variety of emergent macrophytes (system 

dimension, discharge and hydraulic retention time as described above for the SF systems). 

According to the authors, adsorption of E2 and transformation of E2 to E1 appear to be the 

attenuation mechanisms. In a study conducted in Italy, Masi et al., (2004) found estrogen 

attenuation in a hybrid reed bed system with an HSSF cell (160m 2 , depth 0.7m) followed by a 

vertical sub-surface flow bed. The CW system received primary effluent from a medium-size 

hotel (discharge of 17-33 m 3 / -E2 and EE2) 

ranged from 164 to 259ng/l. Estrogen concentration in the HSSF effluent was at least an 

order of magnitude lower (below detection limit of 15ng/l). 

Vertical sub-surface flow wetlands (VSSF) 

In a study conducted in Japan, Song et al., (2009) examined estrogen attenuation in a VSSF 

microcosm tank system (0.5X0.3m) with different depth (7.5, 30, 60cm). The tanks were 

planted with common reed and received tertiary municipal effluent, intermittently (15min. 

intervals, flux of 0.15m 3 /m 2 /day, theoretical HRT of 3.1h). The influent concentration of E1, 

E2 and EE2, was 0.4-10.5, 1.4–9.1, and 0.6-6.6ng/l, respectively. They found an average 

attenuation of ca. 68 (±28), 84 (±15) and 75% (±18) of E1, E2 and EE2, respectively, in a 

tank system filled with a 7.5cm sand layer (porosity – 26%). The authors claim that the 

removal efficiency of estrogens in tanks with a deeper sand layer (30 and 60cm) was lower, 

despite longer residence time (12.4 and 24.8hrs, respectively). They attributed most of the 

estrogen attenuation to biotic processes of microbial degradation and plant uptake, and only a 

little to adsorption. In our recent study (Milstein et al., in preparation) we compared estrogen 

attenuation in mature (4 year) VSSF cells with and without vegetation. The vegetation 

consisted of dense paper reed (Cyperus papyrus), or dense Bermuda grass (Cynodon 

dactylon). The cells (ca. 5X6m, depth 0.55m) received secondary municipal effluent, 

intermittently (1 hr intervals, discharge of 12m 3 /day, HRT of ca. 3hrs). Influent E1 and E2 

concentration were 20.5±7.7 and 7.7±3.1 ng/l, respectively. We found similar high 

attenuation in the vegetated as well as the plant-free cells. More than 90% of E1 was removed 

(to below detection limit -2ng/l) and ca. 60% of E2. In all cells total estrogen removal 

(E2+E1) was >80%. We also conducted controlled laboratory experiments to examine 

estrogen biotransformation under aerobic and hypoxic conditions. Estrogens (E1, E2, E3 or 

____________________________________________________________________________________________________ 


EE2) were spiked into vessels containi 

with double-distilled water supplemented with nutrients (HACH BOD nutrient cat. No. 

14861-66, APHA formulation), in the presence or absence of wetland biofilm (1.5g wetland 

gravel). Significant removal of estrogens was found only in the presence of wetland biofilm 

and was highest under aerobic conditions. For example, aerobic half-life of E2 in filtered 

secondary effluents and in water supplemented with nutrients were 48 and 36hrs, 

respectively, whereas it was an order of magnitude longer under hypoxic conditions. 

Biotransformation of E2 in the presence of wetland biofilm was evident by the appearance 

and accumulation of E1 in the medium. Seven and 15% removal of total estrogens (E2+E1) 

was found under aerobic conditions, in water and filtered effluent, respectively, whereas the 

concentration of estrogens under hypoxic conditions remained unchanged. 

Discussion and conclusions 

Only a few studies on the removal of estrogens or estrogenicity from municipal effluent by 

wetland systems have been reported, all from 2000 on (7 on SF and 4 on SSF). The estrogens 

examined are mostly the natural ones E2 and E1 and a synthetic one EE2. These estrogens 

were commonly found in domestic sewage effluent and are considered the most potent ones 

among the endocrine disruptors (e.g. Khanal et al., 2006). 

In most cases direct evidence for the pathway of estrogen removal is lacking. Measurable 

attenuation as well as failure of significant removal of estrogens was reported in SF wetlands. 

The attenuation of estrogens in SF is attributed mostly to adsorption and biotransformation. It 

is suggested that increasing vegetation density will improve estrogen removal by providing 

greater surface area for biofilm development, enhancing adsorption and biotransformation 

processes (Brix, 1997; Gray and Sedlak, 2005). Decreasing wetland depth so that more water 

flows through the roots and sediments as well as increasing hydraulic retention time were 

also recommended (Gray and Sedlak, 2005). However, achieving high removal of estrogens 

by the latter will require an HRT of months (Metamoros and Bayona, 2008), making most SF 

CW impractical. Additional improvement of estrogen removal in SF wetlands can be attained 

by enhancing oxygenation of the system to support a higher rate of biodegradation 

(Laboratory experiments, Milstein et al., in preparation; Lee and Liu, 2002; Andersen et al., 

2004). We found no evidence for removal of estrogens in SF CW by photo-degradation. In an 

experiment in which E2 was dissolved in secondary effluent and exposed to sunlight for 

24hrs in open glass beakers, only 10% was photo-degraded, compared to none in the dark 

(Mansell et al., 2004). Little or no photo-degradation may be expected in turbid or shaded SF 

systems (Gray and Sedlak, 2005; White et al., 2006). Existing evidence suggests that in subsurface 

flow wetlands estrogens are mostly attenuated under aerobic conditions by 

biotransformation and degradation (Song et al., 2009; Milstein et al., in preparation). This 

conclusion is supported by findings that in conventional wastewater treatment plants too, 

estrogenic compounds are mostly degraded under aerobic, nitrifying conditions (e.g., Liu et 

al., 2009). Indeed, high estrogen removal within a short HRT (hours) was found in vertical 

flow wetlands, which are characterized by aerobic conditions. Lower removal rate may be 

expected in horizontal systems which are characterized by a network of aerobic, hypoxic and 

anoxic zones (Vymazal, 2003). Indeed, no attenuation of estrogens was recorded in both the 

HSSF and SF systems, where hypoxic conditions prevailed (Peterson and Lanning, 2009; 

Milstein et al., in preparation). This conclusion is also supported by the observation that 

estrogen attenuation was reduced in vertical saturated wetlands, compared to that measured in 

unsaturated conditions (Song et al., 2009). High (>90%) removal of estrogen in HSSF CW 

reported by Masi et al. (2004) contradicts the above conclusion. However, Masi et al. (2004) 

examined estrogen removal from primary effluent in which estrogen concentration as well as 

the concentration of suspended solids was extremely high. It is highly probable that the 

___________________________________________________________________________ 


estrogens were adsorbed to suspended solids and removed by TSS filtration and 

sedimentation. It should be noted that the detection limit of estrogens in Masi et al.‘s study 

was 15ng/l; hence the presence of high residual concentration of estrogens in the HSSF 

effluent is possible. 

Although high and rapid attenuation of estrogens in wetlands is attributed mainly to biotic 

processes, adsorption cannot be ruled out as an important mechanism under certain 

conditions. For example, in wetlands with a high surface area and rich in organic substrate 

(Ingerslev and Halling-Sørensen, 2003; White et al., 2006). 

The role played by the vegetation in estrogen removal is unclear. Higher estrogen 

removal in SF wetlands is attributed to vegetation (Gray and Sedlak, 2005; Peterson and 

Lanning, 2009). Song et al., (2009) suggest that the vegetation enhances removal efficiency 

in VSSF by providing a dense root system with a large surface area for biofilm development 

and pollutant adsorption. Moreover, they argue that the vegetation increases oxygen 

concentration in the rhizosphere, releases exudates that are exploited by estrogen degrading 

microorganisms, and takes up and assimilates estrogens in plant tissue. In contrast, we have 

demonstrated a similar efficiency of estrogen removal in plant-free and densely vegetated 

VSSF cells (Milstein et al., in preparation). We therefore suggest that the biofilm coating the 

wetland gravel in VSSF systems can account for most estrogen transformation and 

degradation activity. 

More studies are needed to examine estrogen removal efficiency, particularly in full-scale 

wetlands. Furthermore, studies are needed to elucidate the removal mechanisms and their 

significance in different wetlands types, and under different operation variables and climate 

conditions. Particular attention should be given to quantifying the contribution of the 

vegetation. 

Bibliography 

Andersen, H.R., J. Kjølholt, M. Hansen, F. Stuer-Lauridsen, T.D. Blicher, F. Ingerslev, and 

B. Halling-Sørensen (2004). Degradation of estrogens in sewage treatment processes. 

Environmental Project No. 899. Danish Environmental Protection Agency. 

Bachand, P.A.M. and A.J. Horne (2000 Denitrification in constructed free-water surface 

wetlands: I. Very high nitrate removal rates in a macrocosm study. Ecological 

Engineering, 14:9–15. 

Brix, H. (1997). Do macrophytes play a role in constructed treatment wetlands? Water 

Science and Technology, 35: 11-17. 

Czech, P., K. Weber and D.R. Dietrich (2001). Effect of endocrine modulating substances on 

reproduction in the hermaphroditic snail Lymnaea stagnalis L. Aquatic Toxicology, 

53:103-114. 

Gagné, F., C. Blaise, J. Pellerin, E. Pelletier, M. Douville, S. Gauthier-Clerc, and L. Viglino. 

(2003). Sex alteration in soft-shell clams (Mya arenaria) in an intertidal zone of the St. 

Lawrence River (Quebec, Canada). Comparative Biochemistry and Physiology Part C 

134: 189–198. 

Gray, J.L. and D.L. Sedlak (2005). The fate of estrogenic hormones in an engineered 

treatment wetland with dense macrophytes. Water Environment Research, 77:24-31. 

Hemming, J.M., W.T. Waller, M.C. Chow, N.D. Denslow and B. Venables (2001). 

Assessment of the estrogenicity and toxicity of a domestic wastewater effluent flowing 

through a constructed wetland system using biomarkers in male fathead minnows 

(Pimephales promelas Rafinesque, 1820). Environmental Toxicology and Chemistry, 

20(11): 2268-2275. 

____________________________________________________________________________________________________ 


Huang, C-H. and D.L. Sedlak (2002). Analysis of hormones in municipal wastewater effluent 

and surface water using enzyme-linked immunosorbent assay and gas 

chrmomatography/tandem mass spectrometry. Environmental Toxicology and 

Chemistry, 20 (1):133–139. 

Imfeld, G., M. Braeckevelt, P. Kuschk, and H.H. Richnow (2009). Monitoring and assessing 

processes of organic chemical removal in constructed wetlands. Chemosphere, 74:349- 

362. 

Ingerslev, F. and B. Halling-Sørensen (2003). Evaluation of analytical chemical methods for 

detection of estrogens in the environment. Working report no. 44. Danish Environmental 

Protection Agency. 

Jobling, S., D. Sheahan, J.A. Osborne, P. Mathiessen and J.P. Sumpter (1996). Inhibition of 

testicular growth in rainbow trout (Oncorhynchus mykiss) exposed to estrogenic 

alkylphenolic chemicals. Environmental Toxicity and Chemistry, 15(2):194-202. 

Jobling, S., N. Beresford, M. Nolan, T. Rodgers-Gray, G.C. Brighty, J.P. Sumpter and C.R. 

Tyler (2002). Altered sexual maturation and gamete production in wild Roach (Rutilus 

rutilus) living in rivers that receive treated sewage effluents. Biology of Reproduction, 

66:272-281. 

Jobling, S., D. Casey, T. Rodgers-Gray, J. Oehlmann, U. Schulte-Oehlmann, S. Pawlowski, 

T. Baunbeck. A.P. Turner, and C.R. Tyler. (2004). Comparative responses of mollusks 

and fish to environmental estrogens and an estrogenic effluent. Aquatic Toxicology, 

66:207-222. 

Kadlec, R.H. (1992). Hydrological factors in wetland water treatment. In: Hammer, D.A. 

(ed.), Constructed Wetland for Wastewater Treatment: Municipal, Industrial and 

Agricultural. Lewis Publishers, Chelsea, USA, pp. 25-29. 

Khanal, S.K., B. Xie, M.L. Thompson, S. Sung, S-K. Ong, and J. Van Leeuwen (2006). Fate, 

transport and biodegradation of natural estrogens in the environment and engineered 

systems. Environmental Science and Technology, 40(21):6537-6546. 

Kolodziej, E.P., J.L. Gray and D.L. Sedlak. (2003). Quantification of steroid hormones with 

pheromonal properties in municipal wastewater effluents. Environmental Toxicology and 

Chemistry, 22: 2622-2629. 

Kreuzinger N, M. Clara, B. Strenn and H. Kroiss (2004). Relevance of the sludge retention 

time (SRT) as design criteria for wastewater treatment plants for the removal of 

endocrine disruptors and pharmaceuticals from wastewater. Water Science and 

Technology, 50(5):149–156. 

Lee, H-B and -estradiol and its metabolites by sewage 

bacteria. Water, Air and Soil Pollution, 134:353-368. 

Lintelmann, J., A. Katayama, N. Kurihara, L. Shore and A. Wenzel (2003). Endocrine 

disruptors in the environment (IUPAC Technical report). Pure and Applied Chemistry, 

75(5):631–681. 

Liu, Z.H., Y. Kanjo, and S. Mizutani (2009). Removal mechanisms for endocrine disrupting 

compounds (EDCs) in wastewater treatment — physical means, biodegradation, and 

chemical advanced oxidation: A review. Science of the Total Environment, 407:731-748. 

Mansell, J., J.E. Drewes and T. Rauch (2004). Removal mechanisms of endocrine disrupting 

compounds (steroids) during soil aquifer treatment. Water Science and Technology, 

50(2):229-237. 

Masi, F., G. Conte, L. Lepri, T. Martellini, and M. Del Bubba (2004). Endocrine disrupting 

chemicals (EDCs) and pathogen removal in an hybrid CW system for a tourist facility 

wastewater treatment and reuse. In: Proceedings of the 9 th International Conference on 

Wetland Systems for Water Pollution Control, ASTEE, pp. 461–468. 

___________________________________________________________________________ 


Matamoros, V. and J.M. Bayona (2008). Behavior of emerging pollutants in constructed 

wetland. The Handbook of Environmental Chemistry 5 (S/2): 199-217. Springer-Verlag 

Berlin Heidelberg. 

Milstein, D., D. Avisar and A. Gasith. (In preparation). Biotransformation and biodegradation 

of estrogens by wetland bacteria and removal in pilot scale constructed wetland in Israel. 

Pawlowski, S., T.A. Ternes, M. Bonerz, A.C. Rastall, L. Erdinger and T. Braunbeck. (2004). 

Estrogenicity of solid phase-extracted water samples from two municipal sewage 

treatment plant effluents and river Rhine water using the yeast estrogen screen. 

Toxicology in Vitro, 18:129-138. 

Peterson, E.W and A. Lanning. (2009). Effectiveness of pilot-scale wetland designs in 

removing estrogenic compounds from municipal wastewater plant effluent. 

Environmental Geosciences, 16 (2):61-69. 

Schwarzenbach, R.P., B.I. Escher, K. Fenner, T.B. Hofstetter, C. A. Johnson, U. von Gunten 

and B. Wehrli (2006). The Challenges of micropollutants in aquatic systems. Science, 

313:1072-1077. 

Segner, H., K. Caroll, M. Fenske, C.R. Janssen, G. Maack, D. Pascoe, C. Schäfers, G.F. 

Vanderbergh, M. Watts and A. Wenzel. (2003). Identification of endocrine –disrupting 

effect in aquatic vertebrates and invertebrates: report from the European IDEA project. 

Ecotoxicology and Environmental Safety, 54:302-314. 

Shore, L.S., M. Gurevitz, and M. Shemesh (1993). Estrogen as an environmental pollutant. 

Bulletin of Environmental Contamination and Toxicology, 51:361-366. 

Song, H-L., K. Nakano, T. Taniguchi, M. Nomura and O. Nishimura (2009). Estrogen 

removal from treated municipal effluent in small-scale constructed wetland with different 

depth. Bioresource Technology, 100:2945–2951. 

Tyler, C.R.. and S. Jobling. (2008). Roach, sex, and gender-bending chemicals: The 

feminization of wild fish in English rivers. BioScience, 58(11):1051-1059. 

Vymazal, J. (2003). Types of constructed wetlands. In. Dias, V. and Vymazal, J. (eds). 1 st 

international seminar on the use of aquatic macrophytes for wastewater treatment in 

constructed wetlands. Lisboa, Portugal. pp.35-79. 

White, J.R., M.A. Belmont and C.D. Metcalfe (2006). Pharmaceuticals compounds in 

wastewater: wetland treatment as a potential solution. The Scientific World Journal, 

6:1731-1736. 

Xie, L., Y. Sapozhnikova, O. Bawardi and D. Schlenk. (2004). Evaluation of wetland and 

tertiary wastewater treatments for estrogenicity using in vivo and in vitro assays. 

Archives of Environmental Contamination and Toxicology, 48: 81-86. 

____________________________________________________________________________________________________ 


UPDATE ON CONSTRUCTED WETLAND APPLICATIONS IN ITALY 

Fabio Masi, PhD 

IRIDRA Srl, Via La Marmora 51, 50121, Florence, Italy. (Email: masi@iridra.com) 

Introduction: water situation in Italy 

Italy occupies a long, boot-shaped peninsula, with a total area of 301,318 km² (of which 2,4 

% is water), surrounded on the west by the Tyrrhenian Sea and on the east by the Adriatic 

Sea. It is bounded by France, Switzerland, Austria, and Slovenia to the north. The Apennine 

Mountains form the peninsula‘s backbone; the Alps form its northern boundary. The largest 

of its northern lakes is Garda (143 sq mi; 370 km²); the Po, its principal river, flows from the 

Alps on Italy‘s western border and crosses the Padan plain to the Adriatic Sea. Several 

islands form part of Italy; the largest are Sicily (9,926 sq mi; 25,708 km²) and Sardinia (9,301 

sq mi; 24,090 km²). The Feb 2007 estimate for Population is 59,206,382 with a Density of 

196.2/km². The climate in Italy is highly diverse and can be far from the stereotypical 

Mediterranean climate depending on the location. Most of the inland northern areas of Italy 

(for example Turin, Milan, and Bologna) have a continental climate often classified as Humid 

subtropical climate (Köppen climate classification Cfa). The coastal areas of Liguria and 

most of the peninsula south of Florence generally fit the Mediterranean stereotype (Köppen 

climate classification Csa). The coastal areas of the peninsula can be very different from the 

interior higher altitudes and valleys, particularly during the winter months when the higher 

altitudes tend to be cold, wet, and often snowy. The coastal regions have mild winters and 

warm and generally dry summers, although lowland valleys can be quite hot in summer. 

According to the last available data given by the National Institute on Water Research (IRSA) 

water precipitation in Italy is huge: it ranges from 600 to 1200 mm/year corresponding to 296 

billion of cubic meters that, after evapo-transpiration, leaves 155 billions of cubic meters of 

surface flow and 13 billion of cubic meters of underground flow. Total ―renewable‖ water 

resources, therefore, would be 168 billion cubic meters per year, which means an availability 

―pro-capite‖ of 2800 cubic meters per person, larger than UK or Germany. However, water 

precipitation in Italy occurs mainly during spring and fall, therefore, to use surface flow, a 

large buffer volume – able to store water during rainy seasons – would be needed. Given the 

existing storage capacity along Italian rivers, the amount of available water resources is 

around 50 billions of cubic meters per year. Such distribution is strongly uneven: water 

availability ―per capita‖ ranges between 2000 and 200 m 3 /year. Dryer Regions, as Puglia and 

Sicily had developed in the past important technologies for rain water harvesting and ―wise 

use‖ of water. However, in the first years of the last century huge water transfer networks 

have been realized, such as the ―Acquedotto Pugliese‖ that brings large amount of water from 

Lucania to Puglia. Therefore, original local water storage systems have very often got out of 

use. 

Data on water use in Italy are mainly based on estimations, except for the municipal use, 

that is well known. The last estimation available for the whole water consumption in the 

country dates from 1999 and is summarized in table 1. 

___________________________________________________________________________ 


Table 1 – Water withdrawal in Italy (millions of m 3 /year) 

Municipal Industrial Irrigation Energy Total 

North West 2.268 3.520 8.193 1.863 15.844 

North East 1.453 1.648 5.277 2.538 10.915 

Center 1.618 1.482 970 72 4.142 

South 1.803 879 3.506 36 6.223 

Islands 798 457 2.191 - 3.447 

Italy 7.940 7.986 20.136 4.509 40.571 

Source: IRSA-CNR 1999 

According to National Institute on Water Research (IRSA), around 40 billions of cubic 

meters were withdrawn in 1999 for the different uses. The estimation done in 1999 was 

significantly smaller compared to previous ones, where irrigation uses were accounting for 

more than 25 billions of cubic meters. The new estimation was based on data concerning 

irrigated land that, according to statistics and remote sensing, is decreasing all over Italy: in 

1988 irrigated land covered around 2.9 millions hectares, it decreased around 2.7 in 1999 and 

is now less than 2.5 millions hectares. 

There are no trustable estimations concerning industrial water use, however, several 

sector studies show that industrial consumption in Italy is decreasing, due to the 

delocalisation of heavy industry out of the national borders and to the improved technologies. 

It is commonly agreed among national water experts that industrial water withdrawal 

presently does not exceed 7 millions of cubic meters. 

If irrigation and industrial water use is decreasing country wide, the situation is different 

for municipal water use. More recent data (2005) on municipal water use are now available, 

and show that municipal water withdrawal is still increasing, and it reached 8.7 billions of 

cubic meters per year, with a ―pro capite‖ consumption that ranges between 370 and 165 

l/day. 

From the qualitative point of view, the situation is again very differentiated throughout 

the Country. Surface water quality is almost never particularly bad, but also almost never 

exceptionally good. The largest rivers are normally in fair conditions, even if their quality 

worsens notably during low-flow seasons. 

A great number of ―black spots‖ contribute to the general deterioration of river quality. 

These situations arise in particular when medium or small streams drain areas with high 

urban and industrial concentration. Among the most critical cases we can mention the 

Lambro-Olona-Seveso river network – draining the area of Milan, only recently equipped 

with sewage treatment capacity – the lagoon of Venice, the reaches of Po, Arno and Tevere 

downstream the cities of Turin, Florence and Rome. The presence of industrial districts with 

heavy environmental impact – eg tanning and textile industry in the North, food industry in 

the South – are also an important cause of severe pollution. 

Given the geographic structure of the Country, there are many areas that are vulnerable to 

nutrient pollution, in particular large lakes in northern Italy, artificial reservoirs in southern 

and insular Italy and the upper Adriatic Sea, to which the rivers draining the most densely 

populated and industrialized part of the Country flow. 

From 1976 on, a massive effort has been made in order to provide sewage treatment 

equipment and address water pollution; this effort, though considerable, is largely 

incomplete. While 1/3 of the pollution load is still not treated, water policy so far has been 

able to block, but always never to reverse, the trends of worsening river quality. Some 

remarkable results have been obtained with respect to lakes and even to the Adriatic Sea. In 

____________________________________________________________________________________________________ 


this last case, for example, end-of-pipe treatment and pollution prevention measures have 

reduced by 90% the nutrient load discharged into the Sea. 

Nonetheless, biological and chemical quality of largest rivers does not show signs of 

improvement; while the number of ―unpolluted‖ sites has been dramatically decreasing, thus 

showing that water pollution cannot be considered as a problem only in highly urbanized 

areas. 

Emerging CW projects in Italy 

Beyond the several hundred CWs for domestic and municipal wastewater (most probably 

over 2000 small scale systems, ranging from single house to few thousands inhabitants) 

which are currently operating in Italy, there is a rich variety of different applications of CWs 

for water pollution control, like as agricultural runoff, some advanced tertiary treatment 

plants, raw landfill leachates treatment, highway runoff, etc. A particularly successful sector 

is the agro-industrial application, especially winery and dairy wastewater treatment, with 

several tenths of plants already running or in construction. In the most recent period we 

observed an increasing interest to stormwater management by the involved administrations, 

and often sustainable urban drainage systems, including constructed wetlands, are considered 

with high value; in this sector, also appliances of CWs for CSOs (Combined Sewer 

Overflows) are finding a large audience of interested technicians, and the first realisations are 

on their way to be concluded soon. In the following paragraphs you will find the descriptions 

of some relevant CW systems, already running or under realisation; some of them will be part 

of the Technical Tour programme in the next IWA 12 th International Conference on Wetland 

Systems for Water Pollution Control, which will be held in Venice (Italy), 4-9 October 2010. 

I wish to apologize for the completely personal selection of the cited CW systems and for not 

having inserted a huge number of applications that are currently operating in Italy, surely not 

less relevant than the chosen examples. Constructed wetlands are representing in Italy a 

promising sector for new green-economy approaches, and there is a growing trend for the 

number of involved companies and universities. 

Experimental Farm of the Faculty of Agricultural Sciences, University of Padua. 

1. integrated system of controlled drainage and wetland to reduce agricultural water pollution. 

The facility, extended over a surface of about 6 hectares, reproduces, on scale, a typical 

agricultural basin of the Italian lowlands. The area is divided into 12 plots, where surface and 

pipe drainage are managed by free (all the excess water is eliminated) or controlled (only the 

excess water that can cause problems to crops or soil is eliminated) drainage. The plots 

discharge their effluents into a surface flow wetland for further purification prior to be 

diverted into a stream. The experiment is running since 1996. 

2. buffer strips (BS) to control agricultural water pollution. The following four types of BS, 

interposed between field and ditch, are studied, in comparison with absence of BS (N): 3 m 

wide, with only grass cover (Festuca arundinacea L.) (3F); 3 m wide, composed of one row 

of regularly alternating trees (Platanus hybryda Brot.) and shrubs (Viburnum opulus L.) 

(31S); 6 m wide, composed of a 3 m strip of grass and a row of trees/shrubs (61S); 6 m wide, 

composed of two rows of trees/shrubs. The experiment, running since 1988, is the oldest 

monitored buffer strip system in Italy. Some of the most recent papers produced by the Prof. 

Maurizio Borin‘s group are related to this experimental installation. 

___________________________________________________________________________ 


Integrated system of multifunctional surface wetlands in an agricultural farm, Padua 

The farm is located nearby the Venice Lagoon. The system, realized in a farm of 110 

hectares, is composed by 7 basins treating surface water before their discharge into the Dese 

river very close to the discharge in the Venice lagoon. The total wetland cells surface is 

around 12 hectares. The site is enormously rich in biodiversity and is an astonishing example 

of multi-functions capacity for wetland systems. Also in this case there are published papers 

by Borin et al. 

Surface flow wetland Cà di Mezzo 

The CW system in Ca‘ di Mezzo, located in the municipality of Codevigo, district of Padua, 

at the borders with the municipality of Chioggia, was created a few years ago in order to 

reduce nutrients concentration driven into the Venetian Lagoon by the Altipiano Channel. 

The Ca‘ di Mezzo Wetland was designed to collect the minimum stream flow drained from a 

8700 hectares catchments area that belongs to the Land Reclamation Consortium Adige 

Bacchiglione district and is mainly destined to agricultural use. The water flows from the 

Altipiano Channel into the wetland through an inlet structure equipped with check gates and 

with a second flow stage level control system placed on a downstream bridge. The water is 

then released into the Altipiano Channel through an outlet structure. 

The wetland was designed to treat a few hundreds litres per second, with a mean water 

height that varies from 0.20 to 0.30 m a.s.l. The average water depth is about 1 m. The 

wetland is formed by three independent basins, connected by culverts equipped with control 

structures. 

Areas that are mainly involved in depuration processes are represented by the channel 

network and the wide flood plains zones covered by Phragmites. At the inlet and outlet of the 

wetland there are two couples of sonic level meters located upstream and downstream the 

check gates. Check gates are controlled by a level measuring sensor, that allows to determine 

stored volumes and inlet/outlet discharges. Water levels are available for remote users thanks 

to the Land Reclamation Consortium 

Adige Bacchiglione automatic network. An accurate estimation of the flow rates is 

important not only to determine the hydraulic behaviour and the hydraulic residence time, but 

also to assess the removed load of pollutants. 

____________________________________________________________________________________________________ 


Fusina CW system – Mestre (Venice) 

The Fusina Integrated Project, being developed by the Veneto Region together with SIFA 

Project Financing, involves major changes and upgrades to a large wastewater treatment plant 

treating municipal and industrial wastewater from an extensively populated area and a large 

industrial complex located on the edge of the Venice lagoon. A 110-hectars wetland system, 

designed by Thetis with the consultancy of CH2M Hill specialists, will represent the final 

polishing step that treats wastewater down to the standards enabling its reuse by the nearby 

industrial facilities. 

When construction finishes in 2011, the treatment wetlands at Fusina will be one of, if not 

the largest, in Europe. The project has redeveloped a large dredge spoil area resulting from 

the excavation of the large navigation channel connecting the nearby Porto Marghera 

industrial facilities to the Adriatic sea and will recreate wetland ecosystem functions that the 

Venice Lagoon historically lost to development. A visitors‘ center and passive recreation 

facilities will be incorporated to ensure the community benefits from the wetlands. The 

wetlands will be a marquee example of a sustainable solution to growing water quality issues 

in a world-renowned location. 

Initial Fusina Pilot Wetland System was completed in Summer 2007, and will be used as 

a plant source for the full scale system which is currently under construction 

___________________________________________________________________________ 


Rovigo Province Landfill Site Leachates Treatment – Villadose , Rovigo 

Ecogest Srl, the company which manage the waste cycle in the Rovigo province, has realised 

a natural treatment system for solving their high expenses in transporting the leachates 

produced in their landfill site to a delocalized WWTP; for the difficult nature of this kind of 

wastewater the adopted design is also quite complex. The CWs system is a multistage plant 

which will be able to treat from 10 to 40 m 3 /d and it‘s composed by: a peat filter, a 2 stages 

vertical submerged flow CW, an horizontal submerged flow CW, a Free Water System and 

finally a storage pond. The final effluent can be pumped back to the landfill for capping 

irrigation or discharged in a small ditch. The total area of the treatment plant is about 5800 

m 2 . The total cost for the CWT is about 1,2M €. Considering that at the moment the cost for 

the leachates treatment in a near WWTP is above 30 €/m3, the total investment will be paid 

back in a maximum of 3 years of operation at full capacity. 

Villesse-Gorizia Highway – stormwater treatment by delocalised CW systems 

Within the elaboration of the Detail Plan for the highway connection in Villesse-Gorizia, 

natural treatment technologies have been adopted as appropriate methods to minimize the 

highway runoff impact, to set environmental mitigation zones and to improve infrastructure‘s 

landscaped insertion. The adopted design takes into account the underground water high 

vulnerability; in general terms the treatment train (in total nearly 60 CWs for approximately 

17 Kms of highway) consists in a ―off-line‖ scheme as following: 1) rough screening by a 

mechanical grid, primary physical treatment by a first flush sedimentation tank, followed 

from a high performance degreaser (Coalescence filter); 2) a subsurface horizontal flow 

constructed wetland; 3) a Wet Pond, that receives effluents from the previous sections 

together with the second flush, assuring therefore also to this last amount of lightly polluted 

water a certain degree of treatment; 4) a final vegetated retention area, which acts like an 

infiltration area for groundwater recharge and at the same time like a high efficiency 

evapotranspiration sector. Only in five cases the vegetated retention area was not requested 

because it was possible to discharge in a significant water-body, the Isonzo river; in two of 

this cases, the choice was an on-line treatment, constituted by a sand-removal tank, a 

degreaser and a submerged flow constructed wetland specially designed for stormwater 

events. 

____________________________________________________________________________________________________ 


Municipality of Preganziol (Venice) 

A new social housing settlement (240 pe) includes innovative water systems for buildings, 

like as water saving, grey water use, rain water collection and reuse. Rainwater is harvested 

from roofs and other surfaces (parking area, …) in a separate way and it‘s differently treated 

before its reuse. 

Grey water is treated by a HF CW (14,5 m 3 /d in 232 m 2 ) and then stored for reuse (toilet 

flushing and landscaping), together with the harvested and treated rainwater. Rainwater is 

treated in a 50m 2 VF CW. The water cycle optimisation is saving about 9000 m 3 of potable 

water per year and a 30-35% reduction of the discharged wastewater in the municipal sewer. 

Preganziol is a good example of sustainable building and sustainable water management. 

Natural Systems for Treatment of Combined Sewage Overflow (Gorla Maggiore, 

Capiago Intimiano, Gorgonzola – Milan) 

This project involves the Lambro, Seveso and Olona watershed that are one of the most 

critical areas of the country, in particular on the management of waters. This superficial 

waters are heavily eutrophicated from combined sewer overflows, that on one side has deeply 

altered the hydraulic answer of the territory, increasing the flood peaks, from the other pours 

to the rivers drainage water elevates volumes, that constitute in average 40% of the river bed 

capacity. In combined sewer systems an enhanced treatment of combined sewer overflow 

(CSO) is required, when augmented water quality requirements are demanded or 

conventional CSO treatment does not meet environmental quality standards. Constructed 

wetlands (CWs) have proved to be a highly effective measure to reduce the ecological impact 

of combined sewer overflows (CSOs) on receiving waters. This project aimed to verify the 

design performance of innovative works (first experience in Italy of natural systems for the 

treatment of CSO) from various points of view: technical scientific, procedural- 

___________________________________________________________________________ 


administrative, ―political‖ or of ―acquisition of the consent‖. In September 09 has been 

delivered the final Detail Project for the realisation of the Gorla Maggiore CW system, under 

local funding (by Regional Authority and Cariplo Bank). The CWTP commissioning should 

take place into 2010, as also the start-up of an intensive monitoring programme. 

Constructed Wetlands Treatment Plants for the Treatment of the Municipal 

Wastewater - Municipality of Dicomano (Florence) – Municipality of Vizzola Ticino 

(Varese) 

Wastewaters produced by the whole Dicomano settlement (3.500 p.e.) are treated by a multistage 

CW plant running since september 2003. At the moment, it is the biggest secondary 

treatment Constructed Wetland system in Italy for municipal wastewater. The wastewater, 

after a primary treatment (grid + Imhoff septic tank), flows into an horizontal subsurface flow 

system as secondary treatment (1 st stage), then into a vertical subsurface flow system (2 nd 

stage) and into an horizontal subsurface flow system again (3 rd stage). At least, wastewater is 

received by a free water system as a tertiary treatment (4 th stage). The free water system is 

used as polishing stage for disinfection and enhanced denitrification. It is conceived in order 

to obtain a high-biodiversity area (16 Tuscany‘s autochthon species of vegetation have been 

planted). 

____________________________________________________________________________________________________ 


The CW system treats 525 m 3 of wastewater per day. This system configuration is able to 

perform a good nitrogen removal, especially during summer, when the receiving water body 

has the lowest flow, and achieves the purification targets required by the Italian law (D.L. 

152/06). The system is managed by the main water services contractor of the region, 

Publiacqua Spa, and regularly monitored, at least for the outlet quality as requested by the 

regional regulation. 

The same treatment train has been applied also by a second Municipality is Northern 

Italy; about 350 pe are treated by a CWs system located in Vizzola Ticino – Castel Novate, 

near Varese. 

The application of two stages or multistage CWs systems, with the combination of 

Vertical and Horizontal flow reed beds, is rapidly becoming the most diffuse on the territory, 

but the single house systems which still continue to be single stage and single bed. 

Constructed Wetlands for Tertiary Treatment and Reuse 

Jesi’s Municipal WWTP (Jesi - Ancona) 

Wastewater from the city of Jesi was treated in an activated sludge conventional treatment 

plant. The Jesi Municipality needed to upgrade the treatment capability from 15,000 to 

60,000 p.e. and to reuse a part of the purified wastewater for industrial aims. The upgrading 

of the plant consisted in two new compartments: a nitrification/denitrification technological 

sector; and a final Constructed wetland sector. 

___________________________________________________________________________ 


The CW sector is formed by a sedimentation basin, an horizontal subsurface flow stage 

(about 1 ha) and a free water system stage (about 5 ha). The plant has been realized in a flood 

area near the Esino River and it has been designed as periodic flood proofed. Part of the 

treated water is provided to the near industrial area for reuse by a dual net pipe. 

San Michele di Ganzaria (Catania) 

In Sicily many wastewater treatment plants (WWTPs) of small-medium communities are not 

in operation due to management problems and high O&M costs. Extensive treatment 

processes, such as lagooning and CWs, potentially represent a more appropriate and 

sustainable treatment solution in rural contexts, as in inland areas of Southern Italy where 

climatic conditions and land availability are favourable. A first important experience on 

Sicily has been a subsurface horizontal flow CW for the tertiary treatment (after a secondary 

treatment with trickling filter) of a rural community effluent of about 5,000 people located in 

San Michele di Ganzaria, Eastern Sicily. The system is designed to wastewater reuse for the 

irrigation of olive orchards covering about 150 ha. Since March 2001 a reed bed (for about 

1,100 P.E.) is in operation with a flow rate of 1.75 L/s and a nominal detention time of about 

2 days. The flow path from inlet to outlet is 78 m and the total area is 1,950 m 2 . Mean 

removal efficiencies ranged from 65% to 88% (TSS), 53% to 84% (BOD5), 62% to 80% 

(COD), 14% to 52% (TN), 15% to 45% (TP), 95% to 99.8% (faecal coliforms). The CW unit 

seems to operate efficiently since the starting of operation (from Barbagallo et al., 2002). A 

second bed has been recently added as parallel line, doubling the treatment capacity of the 

system and the amount of treated wastewater (or better ―service water‖) available for 

irrigation. 

____________________________________________________________________________________________________ 


At the same site, the University of Catania has realised an experimental pilot plant that 

consists of four lines of two-stage subsurface flow constructed wetlands for secondary or 

tertiary treatment of municipal wastewater. The first stage, for each line, consists of a 

horizontal flow bed, while in the second stage a vertical flow bed operates for two lines and a 

horizontal flow bed for the other two. Phragmites sp. was used as vegetation in two lines 

while the other two lines are without plants. Several experiments have been conducted there, 

especially for testing the HYDRUS 2D CW model in collaboration with BOKU. 

Constructed Wetlands for Sludge Drying 

Acque S.p.a. – one of the six holding companies for water and wastewater in Tuscany Region 

– manages 152 WWTPs, 130 of which serving less than 5000 people, over a territory of 57 

municipalities. The potential for application of reed beds is therefore very high within the 

controlled territory. Considering all the advantages and good performances reported for reed 

bed systems, in 2004 Acque S.p.a. started to test this technology on a pilot plant. After 

obtaining satisfying and promising results from preliminary experimentation, the company 

decided to adopt reed beds for a set of controlled WWTPs. At present, reed bed systems have 

been already implemented in 6 of them, and 25 new installations are planned for the future. 

All beds are currently fed with aerobically stabilized sludge from domestic activated sludge 

WWTPs. Reed bed systems were easily derived from existing drying beds by planting reeds 

(Phragmites australis) after preparation of the bottom inert and draining layer, and, where 

necessary, after increasing the freeboard of the side walls of the existing drying beds of 1 ÷ 

1.5 m (from Giraldi D., 2009). 

There are some other sludge drying CW systems in Piedmont, mainly in the southern part 

of the region, where several wine factories are equipped with Activated Sludge treatment 

plants for their wastewater management. The Piedmont Regional Authority has subsidised for 

several years, up to 70% of the realisation cost, specifically the application of CWs for sludge 

drying; 

___________________________________________________________________________ 


References and Bibliography 

Barbagallo S., Cirelli G.L., Consoli S., Toscano A. e Barbera A. (2002), Experiences on Constructed 

Wetland as tertiary treatment for wastewater reuse: the case-study of ―S.Michele di Ganzaria‖ 

(Sicilia), Proceedings of 1th International Conference on small wastewater technologies and 

management for the Mediterranean area , Seville, Spain, , pp. 23. 

Giraldi D., Iannelli R., (2009), Short-term water content analysis for the optimization of sludge 

dewatering in dedicated constructed wetlands (reed bed systems). Desalination, (in press). 

Giraldi D., Masciandaro G., Peruzzi E., Bianchi V., Peruzzi P., Ceccanti B., Iannelli R. (2009), 

Hydraulic and biochemical analyses on full scale sludge consolidation reed beds in Tuscany 

(Italy). Wat. Sci. Tech (in press). 

Masi F. (2008), ―Enhanced denitrification by an hybrid HF-FWS CW in large scale wastewater 

treatment plant (Jesi)‖, in ―Wastewater Treatment, Plant Dynamics and Management in 

Constructed and Natural Wetlands‖, by Jan Vymazal (Ed.), Springer, NY, ISBN: 978-1-4020- 

8234-4. 

Masi F. (2009), ―Water reuse and resources recovery: the role of Constructed Wetlands in the Ecosan 

approach‖, Desalination, Vol. 246, pp. 27-34,. 

Peruzzi E., Macci C., Doni S., Masciandaro G., Peruzzi P., Aiello M., Ceccanti B. (2009), Phragmites 

australis for sewage sludges stabilization. Desalination, (in press). 

Toscano A., Langergraber G., Consoli S. and Cirelli G.L. (2009), Modelling pollutant removal in a 

pilot-scale two-stage subsurface flow constructed wetlands. Ecological Engineering. Vol. 35, Issue 

2, 281-289. 

THE TREATMENT WETLAND OF THE MONTREAL BIOSPHERE: 

15 YEARS LATER 

Jacques Brisson 1 * and Gilles VIncent 2 

1 Université de Montréal, Département de sciences biologiques and Institut de recherche en 

biologie végétale (IRBV), 4101 Sherbrooke East, Montreal, Quebec H1X 2B2, Canada. 

2 Jardin botanique de Montréal, 4101 Sherbrooke East, Montreal, Quebec H1X 2B2, Canada. 

*Corresponding author. Tel.: +1 514 872 1862; fax : +1 514 872 9406. 

E-mail: jacques.brisson@umontreal.ca. 

Introduction 

In June 1995, Environment Canada opened a new science museum devoted to public 

education on the environment, water resources and aquatic ecosystems. Built from the 

geodesic structure that was previously hosting the USA pavilion during the 1967 World Fair 

in Montreal, the ―Biosphere‖ is adequately located on Ste-Helene Island, in a highly visited 

park in the middle of the St-Lawrence River. Given the theme of the museum, it seemed 

appropriate to integrate a constructed wetland for wastewater treatment system as part of the 

museum‘s scientific and education program. The project presented important challenges to its 

designers. First, the number of museum‘s visitors, and therefore the quantity of water to be 

treated, was expected to be high with large variation during the year. Second, while the 

technology had already been well established in other parts of the world, its efficiency under 

the harsh climatic conditions of Montreal needed to be evaluated. Third, not only the wetland 

had to be accessible to passers-by in the park as well as to museum‘s visitors, but since a 

restaurant was located only 50m away, no foul odors or malfunction could be tolerated. 

Finally, because of the high publicity and visibility surrounding the opening of the museum, 

____________________________________________________________________________________________________ 


expectations from the public and public authorities were understandably high, putting even 

more pressure for success. 

The design chosen was multi-steps: two parallel reed beds, one shallow surface-flow unit, 

one deep surface-flow unit. Because of its innovative nature, its high visibility and its 

scientific and educational values, the wetland was monitored very extensively for efficiency 

during the first three years, followed by more occasional surveys. Now, 15 years later, the 

Biosphere treatment wetland has proven to be a success; it achieved a high removal 

efficiency that showed no decrease over the years and also completely fulfilled its 

educational mission. In this paper, we report on the design, removal efficiency and dynamics 

of the Biosphere treatment wetland, one of the longest running CWs in Canada. 

Description of the wetland 

For design consideration, discharge assessment was based on the most optimistic projections 

for visitors, estimated to 300 000 per year, with a maximum of 6000 visitors per day. The 

various components of the system are designed to mimic the gradient from wetland edge with 

emergent plants to deeper water with submerged plants, thus optimizing the global 

purification efficiency of the system and its appeal to visitors (Figure 1) (Radoux 2003). 

Pretreatment is achieved by a 45m 3 septic tank at the head of the system. The wastewater 

treated by the CW is thus the overflow of the septic tank (see Table 1 for wastewater 

characteristics). The first CW unit consists of a 400m 2 subsurface flow wetland planted with 

common reed (Phragmites australis). The reed bed is divided in two identical sections 

located side by side. These two sections are independent, and they can be operated 

simultaneously or alternatively. The second unit is a shallow 300m 2 surface flow constructed 

wetland, originally planted with three species each occupying 100m 2 : first bulrush (Scirpus 

lacustris), followed by cattail (Typha latifolia) and then by larger blueflag (Iris versicolor). 

The last unit is a 100m 2 pond designed for polishing purposes. The first part of the pond is a 

shallow 50m 2 section originally planted with water mint (Mentha canadensis) followed by a 

1m deep section of 50m 2 planted with a submerged species, Canada waterweed (Elodea 

canadensis). Sampling mechanisms at the end of each unit, and flow measurement devices at 

the end of the first and last unit, are incorporated in the system for monitoring purposes. 

Finally, display panels explaining the functioning of the wetland are located near the system 

and inside the museum for educational purposes. 

Figure 1. Schematic view of the treatment wetland of the Biosphere, as it was designed. 

___________________________________________________________________________ 


Table 1. Domestic wastewater of the Biosphere Museum, after pre-treatment, based on data from 

1996. 

Number of visitors, 

1996 

87 000 

Precipitation (mm·d -1 ) 2.93 

Influent (m 3 ·d -1 ) 9.8 

pH 7.2 

TSS (mg·L -1 ) 57 

COD (mg·L -1 ) 310 

BOD (mg·L -1 ) 126 

TKN (mg·L -1 ) 90.5 

NH4 (mg·L -1 ) 80.5 

NOx (mg·L -1 ) 23.3 

TP (mg·L -1 ) 10.3 

PO4 

6.6 

15 Years of high removal efficiency 

The treatment system has functioned continuously over the last 15 years. During winter 

(November to March), only the reed beds are in operation, a bypass allowing their effluent to 

reach directly the end of the system without going through the surface flow units. During the 

first three years of operation, removal efficiency was measured twice a month, except in 

winter, where sampling was done once a month. The parameters measured were TSS, DOC, 

BOD, TKN, NH4, NOx, TP, PO4, fecal coliforms (FC), temperature, electric conductivity and 

dissolved oxygen. They were measured at eight sampling points in the system (Figure 1). 

After this initial monitoring demonstrated the high efficiency of the system, further sampling 

and analysis have been occasional over the years, and only during the growing season. 

However, there is a regular inspection of the system for changes in water color, appearance of 

foul odors, or decrease in plant‘s health. 

Inflow averages 9.8 m 3 ·d -1 , with large daily and seasonal variations depending on the 

number of visitors (higher on weekends and in summer). This average is much lower than the 

most optimistic scenario on which the design of the treatment wetland was based. As a result, 

the treatment wetland functions well below its theoretical capacity. HRT is much longer than 

expected, and during the growing season, a good portion of the water is lost through 

evapotranspiration. On occasion, there is no system effluent at all on some summer days with 

no precipitation, high temperature and fewer visitors. 

Removal efficiency has been high for most parameters measured during the whole period 

of monitoring (Table 2). The reed beds are almost entirely responsible for water treatment for 

most pollutants except TKN: water quality at the outlet of the reed beds is so high that further 

removal by the following surface flow wetland units is often negligible (or even negative) for 

TSS, DOC, BOD, NOx, TP and PO4. During the growing season, the reed beds are 

responsible for an average of 50 to 60% TKN removal, while the two SF units are further 

responsible for an additional 25 to 40%. In winter, removal efficiency remained high during 

the first three years of operation except for TKN (data not shown). The lower efficiency in 

TKN removal is obviously due to the fact that the SF wetlands do not contribute since they 

are by-passed. However, there is an additional average of 10% less TKN removal in the reed 

beds relative to their efficiency during the growing season, most likely due to the lower 

temperature (and thus microbial activity) of the wastewater. Removal patterns for NH4 

closely follows those of TKN, both in winter and in the growing season. There is a very high 

phosphorus removal in the reed beds, with no signs of decrease in efficiency over time. 

____________________________________________________________________________________________________ 


Again, the fact that the reed beds have been designed for a larger number of visitors 

contributes to their longevity, delaying the imminence of phosphorus saturation of the bed 

media. 

Table 2. Percentage removal of pollutants for the treatment wetland of the Biosphere Museum, 

Montreal. Results for 1995, 1996, and 1997 are based on yearly averages (excluding winter), with 

removal calculated on a mass balance basis. Results for the other years come from single sampling 

campaigns realized in the growing season, and are based on comparison between inflow-outflow 

concentrations. 

1995 1996 1997 2003 2005 2007 2009 

TSS 63.9 85.8 85.7 85,4 66,7 - 88.0 

BOD 97.0 97.7 97.9 100 100 73 - 

COD 84.9 83.3 83.3 - - - - 

TKN 84.3 86.1 83.9 92.3 95.2 93.2 - 

NH4 79.7 94.5 93.9 94.9 99.5 99.9 98.6 

NOx - 87.0 80.0 - - - 95,2 

TP 97.6 74.0 73.6 100 90,5 96 - 

PO4 99.6 99.0 96.6 99.6 100 100 96.7 

FC 99.9 99.9 99.9 - - - - 

As for plant dynamics, blueflag plantation was not successful in the first SF wetland unit, 

so that more cattail (Typha latifolia) was planted to fill the empty spaces. Over time, cattail 

also slowly gained ground over bulrush so that today, it is largely dominant in this unit. Other 

species of minor importance naturally established (and occasionally disappeared) over time: 

pondweed (Potamogeton sp.), broad-leaf arrowhead (Sagitaria latifolia), etc. The second SF 

wetland unit experienced large changes in plant species composition over time. At the 

beginning, flowering yellow iris (Iris pseudacorus) was planted to replace the water mint, 

which had not survived plantation. Waterweed initially declined and was naturally replaced 

by stonewort (Chara sp.), which is an algae, and other, less abundant plant species, such as 

curly pondweed (Potamogeton crispus) and small pondweed (Potamogeton pusillus). 

However, over time, both cattail and common reed invaded this wetland unit, and they 

represent the dominant species today. There was no effort to prevent these changes since 

overall removal efficiency of the CW was not affected. Apart from a small (and unexplained) 

mortality of common reed in the central portion of one reed bed in 1995, followed by a rapid 

recovery, the reed beds have always shown a dense and healthy plant colony. However, in 

1999, a groundhog (Marmota monax) damaged the membrane while attempting to dig a nest 

on the side of the reed bed. It was thus necessary to remove the reeds and excavate a section 

of the bed to repair the lining, before filling again and replanting. 

Conclusion 

At the time of its creation, it was estimated that the longevity of the reed bed units of the 

treatment wetland would approximately be 15 years, mainly because of saturation in 

phosphorus. A complete rejuvenating of the reed beds, including a replacement of the entire 

substrate and a replanting of common reed, would thus be necessary. We have reached this 

period of 15 years and the removal efficiency shows no sign of decline, nor in phosphorus 

neither in other pollutants. The technology proved to be efficient both in winter and summer. 

In fact, the Biosphere CW is functioning below its full potential since it was designed for a 

larger inflow. Furthermore, the system has been a complete success in terms of its mission as 

a demonstration treatment wetland. It has played an important role in increasing public 

___________________________________________________________________________ 


awareness on the importance of water as a resource, but also on the existence of alternative 

ecological approaches to traditional methods of water treatment. 

Figure 2. Treatment wetland of the Biosphere. Photograph taken in 1996 (J. Brisson). 

Acknowledgements 

The design and construction of the Biosphere CW was the result of a collaborative effort 

between Michel Radoux (Fondation Universitaire Luxembourgeois), Jean-Louis Breton 

(Sodinco Inc.), Marc Marin (<strong>Group</strong>e Steica Inc), Jacques Trottier (Soprin Inc), G. Vincent 

and others. Monitoring was realized by Garba Laouali (IRBV), Linda Dumont (IRBV) and 

the staff from the Biosphere, under the supervision of J. Brisson. We thank the staff from the 

Biosphere, and particularly Yves Bélanger, Harm Sloterdijk and Marie-Hélène Michaud for 

their continuing generosity and assistance. Environment Canada is responsible for the 

Biosphere‘s mission and orientation, museological direction and the building‘s operation. 

References 

Radoux, M. 2003. Les Mosaïques Hiérarchisées d‘Écosystèmes Artificiels - <strong>Group</strong>e de 

recherches MHEA®, Station Expérimentale de Viville – F.U.L - Conception, structure, 

particularités techniques et gestion. 

____________________________________________________________________________________________________ 


NEWS FROM IWA HEADQUARTERS 

Individuals renew your IWA Membership for 2010 online today! 

All the IWA renewals for 2010 have now been sent and IWA would like to encourage our 

members to renew before the end of the year in order to avoid any delay in receiving their 

all-important member benefits! Please renew online at the following link: 

https://www.portlandpress.com/iwa/membership/renewal.cfm 

If you have any queries regarding your membership please feel free to contact us at 

members@iwahq.org 

Don’t be a stranger … 

Ensure that we have your correct contact details at all times. Please update any changes at 

https://www.portlandpress.com/iwa/membership/change.cfm or email 

members@iwahq.org 

___________________________________________________________________________ 


The IWA Water Wiki! 

Call for Contributions 

www.iwawaterwiki.org 

IWA are pleased to announce the launch of a new website – the IWA Water Wiki. This is an 

exciting online project to develop a collaborative platform for the global water community to 

interact and share knowledge online. 

The IWA Water Wiki aims to be THE online reference point for water, wastewater and 

environmental science and management issues. It is a place for water professionals 

worldwide to interact, share information and increase understanding. In addition to reference 

articles the website also offers a set of features designed to enable community discussion and 

interaction. 

The Water Wiki needs your help in order to grow. Here are some ideas for contributing 

material: 

Add a new article – if you have a summary / reference article that is already suitable for the 

Wiki, you can instantly publish online. Go to: 

http://www.iwawaterwiki.org/xwiki/bin/view/Articles/ 

Edit an existing article - ‗Stub‘ articles have been preloaded under different subject 

categories covering a wide range of topics in water. If you would like to write any of these 

articles, click on the article heading that you would like to write on, and start adding your 

material. For example: 

http://www.iwawaterwiki.org/xwiki/bin/view/Articles/Constructedecosystems 

http://www.iwawaterwiki.org/xwiki/bin/view/Articles/ConstructedWetlands 

http://www.iwawaterwiki.org/xwiki/bin/view/Articles/Pollutionmonitoringandcontrol 

Suggest an idea for an article by creating an article with useful starting information that will 

encourage others to complete it. You could add a list of references or a basic explanation of 

your topic as a starting point. For example: 

http://www.iwawaterwiki.org/xwiki/bin/view/Articles/Ecotoxicology 

Copy existing articles from Wikipedia or similar websites. If you have seen a good quality 

water article on Wikipedia you can copy this across to the Water Wiki as long as the 

original source is credited. Wikipedia articles can also be revised and improved in order to 

match the more specific scope of the Water Wiki. This is possible with all websites that have 

a Creative Commons Compatible License. 

For example: http://en.wikipedia.org/wiki/Constructed_wetland 

We‘d love to hear your comments and ideas for this exciting new project. 

For this, or if you have any questions about contributing to the site, please contact: 

Victoria Beddow 

IWA WaterWiki Community Manager 

vbeddow@iwap.co.uk 

____________________________________________________________________________________________________ 


NEW FROM IWA PUBLISHING 

Sediments Contamination and Sustainable Remediation 

Authors: Catherine N. Mulligan, Masaharu Fukue and Yoshio Sato 

The surface water environment can be considered to be an important part of the geoenvironment. 

It is the recipient of not only liquid discharges from surface run-offs, rivers and 

groundwater but also waste discharges from land-based industry, municipal and other 

anthropogenic sources. It is also a vital element in the geo-environment that provides the base 

for life support systems and is a significant resource. The combination of these two large 

factors, with their direct link to human population, makes it an integral part of the 

considerations on the sustainability of the geo-environment and its natural resources. A 

healthy ecosystem ensures that aquatic plants and animals are healthy and that these do not 

pose risks to human health when they form part of the food chain. 

This book discusses the threats to the health of the sediments resulting from discharge of 

pollutants, excessive nutrients and other hazardous substances from anthropogenic activities. 

It examines the impacts observed as a result of these discharges including the presence of 

hazardous materials and the phenomenon of eutrophication. It also examines the remediation 

techniques developed to restore the health of the sediments and how to evaluate the 

remediation technologies using indicators.The problems of sediment contamination are 

developed in addition to how they can be remediated and how the treatments can be 

evaluated. 

Co-Published with CRC Press 

ISBN: 9781843393009 • Pre-order (February 2010) • 359 pages • Hardback 

IWA Members price: £ 48.75 / US$ 97.50 / € 73.13 

http://www.iwapublishing.com/template.cfm?name=isbn9781843393009 

----- 

Analytical Measurements in Aquatic Environments 

Editors: Jacek Namiesnik and Piotr Szefer 

Over the past twenty years, the knowledge and understanding of wastewater treatment have 

Even a cursory perusal of any analytical journal will demonstrate the increasing important of 

trace and ultra-trace analysis. And as instrumentation continues to develop, the definition of 

the term "trace element" will undoubtedly continue to change. Covering the composition and 

underlying properties of freshwater and marine systems, Analytical Measurements in 

Aquatic Environments provides the basis for understanding both. It discusses all aspects of 

analytical protocols from the handling of representative samples to the metrological 

evaluation of specific steps and whole procedures. 

___________________________________________________________________________ 


The book covers: 

� handling of representative samples 

� sample preservation techniques 

� extraction techniques 

� speciation analytics 

� solvent-free sample preparation for analysis 

� application of biotests 

� bioanalytical methods for monitoring 

� green analytical chemistry-application of the concept of sustainability in analytical 

laboratories 

� application of the Life Cycle Assessment approach 

� quality control and quality assurance of analytical results 

� enhanced techniques of sample preparation 

� hyphenated analytical techniques 

Ecotoxicological considerations and the effort to achieve an increasingly accurate description 

of the state of the environment challenge analytical chemists who need to determine 

increasingly lower concentrations of various analytes in samples that have complex and even 

non-homogenous matrices. The newly coined expression "analytics" emphasizes the 

interdisciplinary nature of available methods for obtaining information about material 

systems, with many methods that exceed the strict definition of analytical chemistry. Drawing 

on the disciplines of chemistry, physics, computer science, electronics, material science, and 

chemometrics, this book provides in depth information on the most important problems in 

analytics of samples from aquatic ecosystems. 

ISBN: 9781843393061 • October 2009 • 503 pages • Hardback 



----- 

Groundwater Management in Large River Basins 

Editors: Milan Dimkic, Heinz-Jurgen Brauch and Michael Kavanaugh 

This book reviews the state-of-the-art of groundwater management in large river basins, 

providing an innovative, informative and consistent approach with technical tools for 

planners, decision makers and engineers. 

Groundwater Management in Large River Basins provides comprehensive coverage of 

the basic elements of groundwater management in large river basins, including: 

____________________________________________________________________________________________________ 


� Social, economic and legislative framework, goals, practices and possible tools; 

� Review of EU groundwater legislation and its implementation; 

� Natural groundwater occurrence and natural circumstances and processes; 

� Groundwater management and maintenance issues: 

o Role of natural factors in groundwater management, 

o Different methods of groundwater abstraction and protection 

o Groundwater treatment technologies, 

o Well ageing and maintenance, 

o Nitrate problems, etc. 

� Groundwater modeling as a tool for groundwater assessment; 

� Aquifer restoration; 

� A spectrum of technical appendices for engineers, which address groundwater issues. 

Also included will be appendices intended to support the work of groundwater engineers. 

This book will be of interest to groundwater engineers and planners, as well as lecturers and 

postgraduate and postdoctoral students. 

ISBN: 9781843391906 • November 2008 • 728 pages • Hardback 



----- 

Environmental Hydrogeology 

Second Edition 

Authors: Philip E. LaMoreaux, Mostafa M. Soliman, Bashir A. Memon, James W. 

LaMoreaux & Fakhry A. Assaad 

Headlines continue to blare news of climate change, tangential catastrophic events, and 

dwindling energy resources. Written by respected practitioners, and geared to practitioners 

and students, Environmental Hydrogeology, Second Edition explores the role that 

hydrogeology can play in solving challenging environmental problems. 

New in the Second Edition: 

� Coverage of groundwater recharging 

� Exploration of geology of sink hole prone areas 

� A case study of how salt-water springs were drawn down to manageable levels in the 

Red River 

The authors provide a complete introduction to the fast-growing and evolving field of 

environmental hydrogeology and its future. The second edition includes completely updated 

material and select new case studies. Matching the caliber of coverage found in the previous 

edition, the authors explore topics such as the geological aspects of disposal sites, surface 

water hydrogeology, groundwater hydrology and wells, environmental impacts and the 

hydrological system, and more. They also include types, sources, and properties of waste 

products, and propose waste management programs for groundwater protection. 

___________________________________________________________________________ 


Looming threats such as climate change, water pollution, acid rain, and air pollution extend 

beyond national boundaries and span the gaps between continents. An in-depth understanding 

of hydrogeology will be necessary to resolve these problems. Focusing on science rather than 

the regulations of any particular jurisdiction, the authors explore a variety of solutions and 

practical applications to issues such as groundwater recharging and protection. 

ISBN: 9781843392286 • November 2008 • 374 pages • Hardback 



----- 

Sediment and Contaminant Transport in Surface Waters 

Author: Wilbert J. Lick 

Contaminated bottom sediments and their negative impacts on water quality are a major 

problem in surface waters throughout the United States as well as in many other parts of the 

world. Even after elimination of the primary contaminant sources, these bottom sediments 

will be a major source of contaminants for many years to come. In order to determine 

environmentally-effective and cost-effective remedial actions, the transport and fate of these 

sediments and associated contaminants must be understood and quantified. This book details 

how to best approach contaminated sediments, allowing readers to better assess and address 

water quality and health issues, water body management, and potential remediation methods. 

Sediment and contaminant transport is an enormously rich and complex field that involves 

physical, chemical, and biological processes as well as the mathematical modeling of these 

processes. While many books have been written on these broad topics, Sediment and 

Contaminant Transport in Surface Waters takes a more focused approach, highlighting 

areas that have been recently investigated but not covered thoroughly elsewhere. 

The volume emphasizes the erosion, deposition, flocculation, and transport of fine-grained, 

cohesive sediments; the effects of finite rates of sorption on the transport and fate of 

hydrophobic contaminants; and the effects of major events such as floods and storms. Despite 

these emphases, the overall goal of the text is to present a general description and 

understanding of the transport of sediments and contaminants in surface waters as well as 

procedures to quantitatively predict this transport. 

ISBN: 9781843392293 • October 2008 • 456 pages • Hardback 



----- 

____________________________________________________________________________________________________ 


The Adaptiveness of IWRM 

Analysing European IWRM research 

Authors: Jos G. Timmerman, Claudia Pahl-Wostl, Jorn Moltgen 

The Adaptiveness of IWRM provides new insights and knowledge on the challenges and 

solutions that current water management faces in a situation of complexity and uncertainty. 

Drawing on the available results from a wide range of European research projects under 

several framework programmes, the book provides an overview of the state of the art in 

European research on Integrated Water Resources Management on the topics of Participation, 

Transboundary regimes, Economics, Vulnerability, Climate change, Advanced monitoring, 

Spatial planning, and the Social dimensions of water management. The achievements of EU 

research projects are considered in view of the extent to which IWRM responds to the current 

complexity and uncertainty water management is facing. These achievements are positioned 

in a wider context of worldwide developments in the respective topics which account for the 

future challenges. From this, the book concludes with the required focus of European 

research in the near future and promotes the concept of Adaptive Water Management as the 

preferred direction for the development of IWRM. 

The book presents the achievements of European IWRM research on a range of water 

management topics and offers conclusions and recommendations for research foci that will be 

invaluable to water managers, policy-makers and academic researchers working in the field 

of IWRM. 

This title belongs to the European Water Research Series 

ISBN: 9781843391722 • April 2008 • 156 pages • Paperback 



----- 

Restoring Floodplains in Europe 

Editor: Timothy Moss and Jochen Monstadt 

Floodplains represent some of the most species-rich and endangered ecosystems in Europe. 

They are also hugely important for storing floodwaters, improving water quality, enhancing 

riparian landscapes, producing economic goods (such as timber) and supporting recreational 

pursuits. 

This book explores the reasons behind the discrepancy between growing policy interest in 

floodplains and limited instances of restoration. It presents original, comparative analysis of 

the shifting policy contexts of floodplain restoration in the EU, Germany, France and 

England and Wales, illustrating how recent reforms and re-thinking are creating new 

opportunities for restoring floodplains. Case studies of six schemes to restore floodplains - 

two from each of the countries studied - demonstrate how these opportunities are being 

exploited, but also what difficulties are being encountered by project managers. 

___________________________________________________________________________ 


The findings and recommendations of the book are targeted at researchers and professionals 

engaged in policy development and project implementation at EU, national and local levels in 

fields relevant to river and floodplain restoration. 

ISBN: 9781843390909 • February 2008 • 350 pages • Hardback 



----- 

SELECTED RESEARCH REPORTS 

Feasibility, Design Criteria, and O&M Requirements for Small Scale Constructed 

Wetland Wastewater Treatment Systems 

WERF Report 01-CTS-5 

Authors: S Wallace 

Publication Date: August 2006 • ISBN: 9781843397281 

Pages: 350 • Paperback 



Sustainable Technology for Achieving Very Low Nitrogen and Phosphorus Effluent 

Levels 

WERF Report 02-CTS-1 

Authors: Krishna Pagilla 

Publication Date: September 2008 • ISBN: 9781843397892 




Scientific Review of Cyanide Ecotoxicology and Evaluation of Ambient Water Quality 

Criteria 

WERF Report 01-ECO-1 

Authors: Robert W. Gensemer, David K. DeForest, Rick D. Cardwell, David Dzombak, 

Robert Santore 

Publication Date: December 2007 • ISBN: 9781843397533 




Determination and Significance of Emerging Algal Toxins (Cyanotoxins) 

AwwaRF Report 91170 

Authors: B Nicholson, J Papageorgiou, A Humpage, D Steffensen, P Monis, T Linke, S 

Fanok, G Shaw, G Eaglesham, B Davis, W Wickramasinghe, I Stewart, W Carmichael, and J 

Servaites 

Publication Date: September 2007 • ISBN: 9781843398264 

Pages: 172 • PAY-PER-VIEW ONLY 



____________________________________________________________________________________________________ 


For more information on IWA Publishing products or to buy online visit 

www.iwapublishing.com. Or contact one of IWA Publishing‘s distributors: 

UK, Europe and Rest of World: 

Portland Customer Services 

Commerce Way 

Colchester 

CO2 8HP 

UK 

Tel: +44 (0)1206 796 351 

Fax: +44 (0)1206 799 331 

Email: sales@portland-services.com 

North America: 

BookMasters, Inc. 

P.O. Box 388 

Ashland 

OH 44805 

USA 

Tel: +1 800 247-6553 

(+1 419 281-1802 from Canada) 

Fax: +1 419 281-6883 

Email: order@bookmasters.com 

Koningin Julianaplein 2 (7th floor) 

2595 AA The Hague 

The Netherlands 

Tel: +31 (703)150 792 

Fax: +31 (703)477 005 

Website: http://www.iwahq.org/ 

General e-mail: water@IWAhq.org 

Company registered in England No. 3597005 

Registered Charity (England) No. 1076690 

___________________________________________________________________________

Specialist Group on Use of Macrophytes in Water Pollution ... - IWA

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?