The Indy recently ran a letter titled “What Lies Beneath”…what indeed? The author questions the city’s past actions to improve water quality.
The city installed urban water diversion units beginning in 2002, well ahead of most agencies. These full-time trash capture devices meet imminent regulatory requirements from the San Diego Regional Water Quality Control Board.
Our urban water diversion units, also called CDS units (centrifugal deflection separators), are large underground circular structures (like a very large utility access hole). Urban runoff flows into the CDS units where it spins around a filter. The device directs the filtered water to the sewer system and, ultimately, the wastewater treatment plant. The debris is spun out of the flow and later collected. Much of the water is recycled and reused for irrigation.
The City of Laguna Beach has 25 urban water diversion units that cover 84 percent of the city watersheds. During the critical summer months, water draining to the ocean is captured, cleaned, and redirected into the sewer system. It never reaches the beach. The city checks the CDS units monthly and removes an average of 8 tons of debris each season.
During the winter months, the city’s Wastewater Division field staff can open the diversions in response to a spill that must be captured and prevented from reaching the coastline. Storm flows can be too much to send to the sewer system and are allowed to bypass the diversion units to prevent flooding. The nonprofit group, Heal the Bay, recently awarded Laguna Beach’s city beaches straight A’s during dry weather conditions. The city earned these grades because sound protections are in place to prevent pollution from reaching the coastline waters.
David Shissler, Laguna Beach Director of Water Quality
