The City of Los Angeles will divert the Hyperion Water Reclamation Plant's effluent from its 5-mile outfall to its auxiliary 1-mile outfall. The diversion will occur from September 21 - October 26, 2015. Effluent will be switched from the 5-mile outfall to the 1-mile outfall with an average of 230 million gallons per day (mgd) over this 5 week period.

• LA Sanitation's (LASAN) Environmental Monitoring Division has developed an enhanced and comprehensive effluent and receiving water monitoring plan.
• The monitoring plan is in compliance with the Regional Water Quality Control Board and the Environmental Protection Agency permit requirements and will provide an assessment of environmental impacts.

Effluent Monitoring

• Chronic Toxicity Testing (most sensitive species, red abalone) - once per week
• Conventional Chemistry/Instrumental Chemistry - 97 compounds/parameters. Sampling frequency range daily to once per month during the diversion.

Shoreline Monitoring

• Total Chlorine Residual (TCR)- Tracks the plume and measures disinfection dosage and exposure time effectiveness.
• Microbiology- Measures fecal indicator bacteria for human health risk (safe to swim) and to determine the effectiveness of the disinfection process. 

Nearshore/Offshore Monitoring

• Total Chlorine Residual (TCR)- Tracks the plume and measures disinfection dosage and exposure time effectiveness.
• Microbiology- Measures fecal indicator bacteria for human health risk (safe to swim) and to determine the effectiveness of the disinfection process.
• Nutrients-Measures concentrations of multiple nutrient compounds for phytoplankton community change implications.
• Phytoplankton (Harmful Algal Blooms)- Investigate community composition changes resulting from increased nutrients into the nearshore environment.
• Benthic Macrofauna/Sediment Chemistry- Assess the toxicity of sediments near outfall as a result of the diversion.

• High-Frequency Radar (HFR) UCSD/SIO/SCCOOS - Estimates near real-time surface current water trajectories using Lagrangian particle tracking algorithm applied to HFR surface current velocity (speed and direction) vectors.
• Space-based Vehicles (Satellites) NASA/JPL - Intermittent data acquisition from a variety of satellite vehicles and sensors (e.g., Synthetic Aperture Radar) to hindcast plume magnitude and location.
• Current Drifters UCSB- GPS-equipped, dragged floats that provide real-time surface current velocities during both pre-diversion and diversion periods.
• Wirewalker UCSD/SIO - Continuous, wave-powered vertical profiler with CTD (conductivity-temperature-depth)to measure vertical location and thickness of the plume at the outfall in a mooring configuration.
• Continuous Surface Mapping CLAEMD - Tracks and delineates the plume (2D) with multiple water quality parameters using a YSI 6600 V2 data sonde (or probe) and a flow-through system.
• Profiling CTD CLAEMD - Multiple parameter instrument package for vertical profiling to track and delineate the plume (3D) with sensors for salinity, temperature, pressure (depth), colored dissolved organic matter (CDOM), chlorophyll-a, transmissivity (turbidity/water clarity), pH and dissolved oxygen.
• Website UCSD/SIO/SCCOOS - Project information portal for public, scientists, managers and regulators with near real-time data posting and a secure data upload.