TGPC: Greater Wellington letter to Chair, PCTG BOI - Attachment 2

,Literature review of Porirua Harbour and catchmentAppendix 2: Annotated BibliographyNutrients in Takapu Stream sourced from farm runoff, in Porirua Stream from urbanstormwater or possibly sewer leaks. Macroinvertebrate Community Index in declinesince 1987Cameron, D. (1994). Baseline warer qwal^b, of Rivers and siredIlls ill Ihe Well^^8101? Region -1993/1994. Consents and Investigations, Wellington Regional Council, Publication N' WRC/Cl-1-94124Annual water quality survey results of streams and rivers in the Wellington Region asinitiated with Cameron (1988). Similar to Cameron and Wall(1992). Measured 4 sitesalong the HOTokiri Stream, 4 along the Pauatahanui Stream and 5 along POTirua Stream.HOTokiri Stream allsites 'suitable'. Pauatahanui Stream 3 sites 'doubtful', I 'suitable'Porirua Stream 4 sites doubtful' and the Takapu Stream site improved to suitable.Porirua Stream identified as an area with high concentrations of phosphorus, sourcedfrom urban stormwater. Lists macroinvertebrates foundCameron, D. and Sand0 (1990). Boseliite water quality of rivers rind sirenins in Ihe Well^I^gionRegion 1988-89. Water Resources Department, Wellington Regional Council, Technical Report90-I.Annual water quality survey results of streams and rivers in the Wellington Region asinitiated with Cameron (1988), and is a similar study except with no map of general landuseSite locations changed since Cameron (1988) study. Measured 8 sites along theHOTokiri Stream, 6 along the Pauatahanui Stream and 7 along POTirua Stream. HorokiriStream occasional unsightly brown coating of diatoms and filamentous algae, 'suitable'along length except one site which is 'doubtful'. Change probably due to increased BODcaused by algae. Pauatahanui Stream high faecal conforms due to disposal of piggeryeffluent on the Haywards Hill branch, a recently completed oxidation pond system shouldremedy this, all sites doubtful'. POTirua Stream all sites 'doubtful', occasional industrialspills recorded. Compared with 87188 data, faecal conform counts have significantlyincreased on all streamsCameron, D. and R. Wall(1992). Basel^Ile woier quality of rivers und sireniiis ill Ihe Well^I^8101iRegion 1991 -92. Consents and Investigations, Welling10n Regional Council, WRC/Cl-T-92122Annual water quality survey results of streams and rivers in the Wellington Region asinitiated in Cameron (1988). Similar to Cameron (1991) but compares data fromprevious years and presents analysis and discussion of dissolved reactive phosphorus andnitrate-nitrogen. Horokiri Stream all sites returned to 'suitable'. Pauatahanui Streamimproved, all but I site ('doubtful') are 'suitable'. POTirua Stream improvement 5upstream sites 'suitable and 2 downstream doubtful'. Takapu Stream identified as an areawith high concentrations of nutrients from farm runoff, likely to cause nuisance algalgrowths. Compared with 90191 data, faecal conform counts have dropped onPauatahanui and Horokiri Streams. pH in POTirua has dropped from the basic to normalrange.Kerinedy, P. and I. Gadd (2006). Urban stormwaier quality in the Greater Wellington Region:is itthe same as elsewhere? Kingett Mitchell Ltd. prepared for the Greater Wellington RegionalCouncilElevated concentrations of metals (copper, lead and zinc) near Semple St drain, draininginto the Onepoto arm of POTirua Harbour.Reportfor Porirua City Council & Wellington City CouncilBlaschke and Rutherford Environmental ConsultantsFebruary 201017