La gestion intégrée des eaux pluviales - AQUA-ADD Interreg IVC ...

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Urban
rainwater
A resource
to be used
Place doctors Mérieux
Lyon
Regarded as a random phenomenon and a constraint to be
managed, urban rainwater has historically been managed
separately from other elements in the urban water cycle.
This approach is today reaching its limits and, in parallel,
we have become aware of the rich resource which rainwater
could represent. Refreshment for the city, irrigation of planted
landscaped spaces, climatisation of buildings with green
roofs ... It can be used in many ways, but new approaches
are called for.
Moving beyond exclusively technical responses
With the urban development of the past few decades, the soil
of the agglomeration has become increasingly less permeable,
and now no longer allows sufficient percolation of rainwater
into the water table. The challenge facing us today and tomorrow
consists of favouring the re-infiltration of this water into the
subsoil, limiting the flood risk, and supplying and conserving
the agglomeration’s water resources.
Adapting to the territory
To be effective, these systems need to take account of the reality
in the territories. The topography, hydrology and geology can
help us to find innovative solutions. Thus, Grand Lyon has
3 sectors. The dense urban centre has a highly developed
combined sewer network which can be optimised. In West
Lyon, with its poorly infiltrating rocky land, a separate network
needs to be developed with rainwater being discharged into
its streams. Lying on permeable land without a hydrographical
network, East Lyon allows rainwater to percolate into the land.
The “Development and Rainwater” guides and the reference work
for the design and management of public spaces
Grand Lyon has developed tools to help planners integrate rainwater
management from the design stage of a project. The “Development
and Rainwater” guides explain the management rules and the
procedures to be followed. The reference work on the “Design
and Management of Public Spaces” specifies the highway design
rules, and the types of materials for public spaces or other
developments. In producing these tools, Grand Lyon wished
to encourage the various trades to work in complete synergy,
in order to move towards an integrated rainwater management.
The guides and the reference work can be found
on Grand Lyon’s website: grandlyon.com
A votre service > Eau et assainissement > Gestion des eaux pluviales
Working on the transversality of services
In every development project undertaken in its territory,
Grand Lyon’s Water Department works in close collaboration
with Grand Lyon’s Highways, Urban Design and Sanitation
Departments, and likewise all the other parties involved
in the development. By jointly considering the issues of water,
air, noise, climate, well-being and economic development,
they put in place sustainable solutions, arising from the synergy
of all their skills.