Wastewater Discharge

Wastewater and sewage spilling into the San Diego ocean has become a common occurrence over the years. Infact, levels have gotten so high that the Environmental Protection Agency (EPA) has proposed a plan to lower wastewater discharges into the ocean, thus improving water quality.

Sewage Spills

Sewage spills into the San Diego ocean occur as a result of burst pipes in the antiquated system, usually as a consequence of increased water volume caused by rainwater. These spillages from pipes or treatment plants lead to the release of raw or partially treated wastewater into San Diego’s coastal areas, lagoons and creeks.

The spills contain a mixture of pathogens (viruses and bacteria), nutrients (phosphorus and nitrogen) and a suite of chemicals. These pathogens can be harmful to wildlife and make the water unsafe for swimming, putting the health of those who come into contact with the water at risk.

Phosphorus and nitrogen are key to helping animals and plants grow and develop. However, there is excessive growth of photosynthetic organisms when the concentrations in water rise, which interrupts the levels of oxygen in the water available to aquatic animals - therefore, some forms of phosphorus and nitrogen are toxic to animals.

Improving the Lifespan of Aquatic Animals

Improving the Lifespan of Aquatic AnimalsIn order to stop spillages, improve water quality and increase the lifespan of aquatic animals, the city and environmental organisations signed an agreement for San Diego to implement a potable water reuse plan.

Eventually, this plan will divert over 80 million gallons of wastewater each day from ocean discharges to an advanced water purification facility. Once the facility has been built, it will send highly purified water to local drinking water reservoirs or other reuse projects.

San Diego is highly committed to lowering sewage and pollutant discharge through its ocean outfall.

The Plan

The EPA plan includes a big step in protecting the health of coastal waters and improving the city’s drought resilience.

San Diego’s regional water board released National Pollutant Discharge Elimination System permits with EPA to make sure all water quality standards are successfully met in state waters. The plan is also aiming to maintain its requirements to reach the water quality standards for the next few years - including features of the Pure Water San Diego program to enhance water reuse and lower discharge into the ocean.

The Pure Water San Diego program uses an integrated water planning approach and ensures San Diego will invest in an advanced water purification facility to transform wastewater into a resource which lowers the need to import water, addresses ocean water quality and helps meets water supply needs.


Belmar Technologies design, build, install, commission and service complete industrial wastewater treatment systems for a wide range of sectors. For more information or to discuss our services further, please feel free to get in touch either by email to mail@belmartechnologies.co.uk or by calling +44 (0) 1327 586 008.