The City of New Orleans is responsible for maintaining and testing the groundwater for potential pollution for several closed landfills and incinerator sites which it owns. These sites were used to receive municipal solid waste. Maintenance includes mowing, repairing, and replacing damaged fencing, gates, and locks and, in some cases repairing clay caps and gravel roadways. In addition, if illegal dumping is observed, it will be reported to the Dept. of Sanitation for removal.
When barrels containing hazardous substances are dumped in the rights-of-way, the City is responsible for the safe removal and disposal or them. The City of New Orleans’ municipal separate storm sewer system (MS4) is composed of storm drains (called catch basins) along streets which are connected to underground pipes. The system is designed to gather stormwater from built-up areas and discharge it, without treatment, into Lake Pontchartrain. It's called a separate system because it is not connected to the sanitary sewer system which drains wastewater from inside a home or business to the City’s sewage treatment facility.
Since there is no treatment for pollutants that may be in stormwater runoff, they can also enter Lake Pontchartrain. Types of pollutants include sediment (dirt), pesticides, fertilizers, motor oil, grease, paint, household chemicals, trash and construction site materials and debris. These pollutants can harm the ecology of the Lake.
The Louisiana Department of Environmental Quality requires the City to comply with the regulations in a Municipal Separate Storm Sewer System (MS4) permit. The permit
requires the City to develop, implement, and enforce a program to reduce pollutants in stormwater.