Clean Water Program
COVID-19 Update: Don’t flush disinfecting wipes
As we rush to sanitize our environs, do not flush disinfecting wipes or paper towels down the toilet but to discard them in the trash. Even “flushable” wipes can clog sewer lines and lead to overflows at wastewater treatment facilities. Wipes are a leading cause of sewer system backups; spills can contaminate our lagoons and the ocean.
The City of Del Mar’s Clean Water Program protects and enhances the quality of our lagoons, beaches, and the Pacific Ocean. For Del Mar, clean water ties directly to quality of life and is key not only to our health and recreation but to property values, tourism and visitor spending. Clean water is for everyone. Accordingly, the City’s obligation to prevent pollutants from entering the watershed is regulated by state and federal laws.
Clean Water: It’s our responsibility and it’s the law
Del Mar’s federally-issued MS4 permit – that’s short for “Municipal Separate Storm Sewer System” – allows the city to discharge storm water from its collection system into waters of the United States. Under this permit, storm water – and only storm water – is allowed for release into the ocean and lagoons. Unauthorized connections or discharges into gutters and storm drains are prohibited and could result in enforcement actions.
A second, federal permit -- the NPDES permit, for National Pollutant Discharge Elimination System --typically allows a licensee like the City to discharge specified quantities of pollutants into waterways under certain conditions.
As a licensee subject to oversight by the Regional Water Quality Control Board, the City of Del Mar prohibits all non-storm water discharges unless they are authorized by a separate NPDES permit or qualify as a conditional discharge.
In Del Mar, most prohibited discharges come from: irrigation runoff; vehicle washing; hosing down or pressure-washing streets, sidewalks or parking lots; swimming pool discharges, or sewer overflows.
Pollution prevention: If you see something, say something
Del Mar’s Clean Water Program owes its success to residents, property owners and City staff working together to share information and report suspected violations. Immediately contact the Clean Water Program if you witness the release of runoff into streets, sidewalks, gutters and storm drains from activities such as: over-irrigation; vehicle washing; driveway or sidewalk washing, or washing of restaurant mats or equipment. At construction sites, all materials and sediment must remain on the job site and off of the public right-of-way.
When infrastructure fails
Aging infrastructure presents major challenges to the Clean Water Program.
Much of the corrugated metal pipe – or CMP -- that conveys Del Mar’s storm water runoff is decades old (left).
During the 1960s, CMP was the material of choice for storm drain systems. CMP has fallen short of expectations for its durability, however, and across the country agencies are reporting that the old pipe is failing.
In Del Mar, a recent survey of the storm drain system identified corrosion just in time to avoid substantial damage to Carmel Valley Road and Camino del Mar.
The assessment identified segments of CMP that should be replaced with reinforced concrete pipe (left).
Near Del Mar, the City of San Diego is replacing 1,000 feet of corrugated metal pipe as part of an emergency repair project in Crest Canyon.The failure, combined with heavy rains, led to the formation of a sinkhole (left).
Downstream, the failure caused a major release of sediment into San Dieguito Lagoon.
In Crest Canyon, popular hiking trails are closed during repairs.