Présentations Colloques

Oral Presentation
6.02
Session 6.02: Treated WasteWater REUSE for groundwater recharge: addressing the challenge
Marta Hernandez Garcia
Managed Aquifer Recharge in Barcelona with reclaimed and pre-potable water- towards a practical application in urban water supply
Barcelona metropolitan area is already well-known by hydrogeologists working in Managed Aquifer Recharge (MAR). Four different techniques co-exist in a relatively small area, including- infiltration ponds, river bed scarification, hydraulic barrier against sea water intrusion and Aquifer Storage and Recovery (ASR) wells. Despite the amount of existing publications and projects demonstrating its feasibility, MAR is still perceived by operators and administration as an uncertain technology and difficult full-scale solution for the water supply in Barcelona area.**The EU funded project DESSIN (2014-2017), aims at demonstrating the technical feasibility of injecting and recovering pre-potable water. The demonstration phase takes place in one of the reversible wells of Sant Joan Despí Drinking Water Treatment Plant (Barcelona, Spain), equipped with injection and recovery system (36 and 220 L s respectively). The demo site is located in one of the most transmissive aquifers registered (there are records of hydraulic transmissivity up to 15.000 m2 d). The injection water comes from an intermediate stage of the drinking water treatment plant, after sand filtration. **First results are already available, including a comprehensive analysis of international guidelines and recommendations for ASR using non-potable water, evaluation of risks of sand filtered water as injection water and pilot experiment simulating ASR. An innovative method to simulate the well screen has been developed and tested, allowing the quantification of extracellular polysaccharides along the injection period. **The project will open the discussion about the practical implementation of MAR systems, and specially ASR in Barcelona area. These techniques could be considered as an alternative in the renovation of drinking water production schemes.
Spain