EWA’s ocean discharge permit (National Pollutant Discharge Elimination System – NPDES - permit), issued by the San Diego Regional Water Quality Control Board, establishes discharge limits and monitoring requirements to ensure protection of the ocean environment.  EWA’s laboratory, which is certified through the California Department of Health Services-Environmental Laboratory Accreditation Program, analyzes more than 2,000 ocean samples per year.  Testing results demonstrate that effluent from the EWPCF meets regulatory standards and is not negatively impacting local water quality. A copy of EWA's annual NPDES report. which contains monitoring data, can be found here.

Surf Zone Monitoring
To assess bacteriological conditions in areas used for body contact activities, samples are collected weekly at five stations along the shoreline in the vicinity of the ocean outfall.  These samples are tested for three indicator bacteria (total coliform, fecal coliform and enterococcus) that are used to assess the safety of recreational waters for human contact.  A minimum of 1,300 such tests are performed annually.

Near Shore Monitoring
To assess bacteriological conditions in areas used for body contact activities and where shellfish and/or kelp may be harvested, samples are collected monthly at five near shore monitoring stations.  Three stations are located at the 30-foot depth contours opposite the surf zone stations and the other two stations are located at the offshore edge of the kelp beds (one north and one south of the outfall). Samples are collected at the surface and are tested for three indicator bacteria.  A minimum of 300 such tests are performed annually.

Offshore Monitoring
To determine compliance with water quality objectives of the California Ocean Plan and to determine if EWA’s discharge is causing any significant impacts to water quality, samples are collected monthly at five offshore monitoring stations. The stations are located in the proximity of the outfall diffuser (where treated wastewater is discharged into the ocean).  Samples are collected at the surface and at a depth of 20 meters, and are tested for three indicator bacteria.  A minimum of 480 such tests are performed annually.

Intensive Monitoring
EWA is required to perform the following intensive ocean monitoring activities once during each five-year NPDES permit cycle:
Benthic monitoring – Sediment samples are collected at all offshore monitoring stations and analyzed to assess the level of pollutants and the type and quantity of organisms they contain.
Demarsal fish and macroinvertebrates monitoring – An assessment of the population of such organisms and the bioaccumulation of toxic pollutants is conducted to determine whether a significant difference exists between those populations near the outfall diffuser and those in reference areas.

Regional Monitoring
EWA is required to participate in the following regional monitoring programs that assess water quality throughout the San Diego region:
Region 9 Kelp Consortium – This organization performs quarterly aerial flyovers of the kelp beds and uses infrared photography to measure the canopy surface area.  Results are compared on an annual basis to assess the health and lifecycle of the kelp beds.
SCCWRP Bight Study – Every five years, the Southern California Coastal Water Research Project (SCCWRP) coordinates a study of water quality in the Southern California Bight (an area from Point Conception to Ensenada, Mexico).  This collaborative study, which was first conducted in 1994, brings ocean dischargers and researchers together to focus their efforts in a cost-effective manner for maximum scientific benefit.  The Bight Study is designed to understand the effects of human activity on the marine environment in the areas of coastal ecology, shoreline microbiology, offshore water quality, rocky reefs and areas of special biological significance.