Throughout Europe’s urban areas, alarmingly high numbers of rivers and streams are polluted by misconnected pipes at domestic properties.  Often unbeknown to home-owners, some washing machines, dishwashers and kitchen sinks empty into surface water drainage systems instead of sewers, causing significant, persistent damage to the biodiversity and ecosystems of urban waterways.

To address this issue in Dublin, South Dublin County Council and Dún Laoghaire-Rathdown County Council joined forces to identify misconnections and improve water quality in two river catchment areas in the county.  The project attracted funding from the European Union’s LIFE programme and aimed to develop a best practice approach for finding misconnections and improving water quality that could be replicated easily across Ireland and Europe. 

Targeted action to find misconnected appliances
Using the ArcGIS process, council employees in Dublin no longer waste time visiting properties that are unlikely to have a misconnection and instead focus their efforts in the locations that are most likely to lead to an opportunity to reduce pollution.  “The driver for the project is always the quality of the rivers,” emphasises Briana Shiels, GIS Officer at South Dublin County Council.  “ArcGIS enables us to find as many houses as possible with misconnected appliances, as efficiently as possible, to help Dublin’s rivers reach a good standard of water quality.”

Significant reduction in the discharge of polluted water
As a direct result of the Dublin Urban Rivers LIFE project, action has been taken to remove over 1,000 misconnected devices at 500+ properties, and far less washing detergent is now reaching Dublin’s rivers.  “Householder repairs are helping to improve water quality and aquatic biodiversity in local rivers with over 85% of the misconnections fixed to date,” says Shiels.  “We estimate that we have removed around 2 million litres of polluted waste water per year from two river catchments, using our ArcGIS process.”

50% cost saving from more efficient process
In two and a half years, the project team has carried out over 8,300 house inspections, and the rate of finding a misconnection is double the number that would have been possible using the previous indiscriminate door-to-door approach.  By extension, this also means that the cost of finding misconnections, over this same period, reduced by 50%, delivering a better return on investment.  “On average 8% of domestic properties in Dublin have a misconnection and the DURL Project has identified a misconnection rate of greater than 30% in some housing estates,” explains Lorainne Beirne, Dublin Urban Rivers LIFE Project Co-ordinator.  "We now have a better system to pinpoint these properties and take action far more efficiently with ArcGIS.”

Seamless capture and sharing of real-time data
The inherent integration of ArcGIS products enables data to be seamlessly captured and shared in real-time.  Furthermore, ArcGIS Online Dashboards provide a highly effective way to share key project metrics, keeping senior managers and stakeholders abreast of progress.  “Project information is transparent to everyone working on the project, whether in the field or in the office,” says Shiels.

Easily replicated solution for use elsewhere 
The project team has now created a ‘lite’ version of its ArcGIS water management solution that can be easily picked up and used as a foundation stone by other local authorities.  “Custom-written solutions can cost hundreds of thousands of Euros and be a disaster,” muses Beirne.  “With ArcGIS, we have built a replicable, standard solution with products that most local authorities in Ireland know and use already.”