The excess clear water from I/I problems uses sanitary sewer capacity needed for wastewater. The result is sewer backups and increased costs (about $300 to $400 million annually) for needlessly putting clear water through the wastewater treatment process.
The Metropolitan Council Environmental Services (MCES), which provides regional wastewater collection and treatment for the metropolitan area, requires communities with excess I/I to invest in local reduction remedies such as disconnecting sump pumps and foundation drains from sanitary sewers and repairing leaky sanitary sewer pipes. Such actions will cost roughly $150 million, instead of the nearly $1 billion it would cost to build additional sewer infrastructure to provide capacity during big rain storms. To urge compliance, MCES incorporated surcharges for communities with excess I/I.
Golden Valley was identified as a contributor of excess I/I and is working to resolve the problem.