A performing Depollution System for Runoff water preserving Biodiversity

PROJECT DESCRIPTION

BACKGROUND

Water quality is a key environmental challenge for European cities. It is estimated that 20% of European surface waters are threatened by pollution (from agricultural practices, landfills, industrial and urban waste). Rainwater contributes to a reduction in the quality of aquatic ecosystems. Many studies have highlighted the importance of urban wet weather pollution that can be greater than wastewater pollution because of the high concentrations of metals, suspended solids and hydrocarbons. In particular, the runoff water from high-traffic roads contributes to heavy pollutant loads and the treatment of this kind of pollution in the dissolved phase is not properly addressed in traditional rainwater depollution systems.

In Paris, despite the successive implementation of plans to reduce sewage pollution over the last 25 years, significant efforts are still needed to achieve a good ecological status of the Seine's water. In particular, action is needed to tackle the pollutants in rainwater runoff. Emblematic of these issues, the storm-water drain of Bugeaud crosses the well-known park, the Bois de Boulogne, and directly discharges into the Seine the runoff from a nearby heavy-traffic road. This is in contravention of the EU's Water Framework Directive and Urban Wastewater Directive.

OBJECTIVES

LIFE-ADSORB will establish a demonstration site at the Bois De Boulogne to prove the efficiency of a novel means of reducing pollution in rainwater runoff into the natural environment. This will focus on reducing levels of metals, suspended matter, hydrocarbons and other toxic compounds (phthalates, alkylphenols, perfluorinated compounds, etc.) found in storm water runoff from roads. The choice of demonstration site in a public park that is classified as 'natural heritage to be protected' is designed to show that improved management of polluted rainwater is compatible with the preservation of natural heritage and biodiversity.

The project has designed a solution that can be adapted to existing infrastructure and replicated in both densely populated and rural areas, as well as being suitable for industrial applications. It will share its results with European actors involved in the improvement of water quality. This will add to the knowledge base for the development, follow-up and evaluation of initiatives related to rain water depollution. Thus, LIFE ADSORB will contribute to the implementation of the Water Framework Directive, Urban Wastewater Directive, Floods Directive and Bathing Water Directive.

 

RESULTS

Expected results:

A new prototype treatment infrastructure, combining several effective technical solutions related to retention and depollution, with key recommendations (directly issued from the simulation performed on the prototype) on how to upgrade its functioning;

An operational design-support tool to adapt the infrastructure and the adsorbent material to other territories and sectors;

Recommendations for technology transfer based on monitoring of performance;

Improved quality of treated runoff water: a 95% reduction in the concentration of mineral and organic micropollutants; a 12.8 tonnes/year reduction in the flow of suspended matter; a substantial reduction in bacteria concentrations; a 98% reduction in the frequency of discharge of wastewater into the Seine;

Improving the quality of treated water will allow its reuse, thus creating a new water resource (potentially: 200 000 m3/year);

A 10% increase in the Ecological Quality Indicators (EcoQOs) of the site through the revegetation of the prototype (planted filter) and other supporting measures to promote species diversity.