solar panels and blue sky with clouds
Lancaster Clean Power Utility Solar Site Permitting
November 11, 2019
Pond 20 Wetland Mitigation Bank
December 9, 2019
San Marcos Highlands Habitat Mitigation Implementation
January 25, 2021
Joseph P. Martinez Park Master Plan
March 9, 2021

Lake San Marcos Biological Investigations & Litigation Support

San Marcos, CA

For more than nine years, Great Ecology conducted biological and hydrological investigations of Lake San Marcos, a 303(d)-listed nutrient-impaired water body in Southern California, in fulfillment of Investigative Order. No. R9-2011-0033 and in support of litigation.
Great Ecology staff worked closely with the lake owner, Regional Water Quality Control Board, public agency defendants, and the lake homeowner community to characterize the site through field sampling and laboratory analyses as part of an agency-approved monitoring plan. This included collecting water quality and dry and wet stormwater data; conducting bathymetric surveys and sediment nutrient flux surveys; and evaluating watershed hydrology and nutrient sources. In addition, Great Ecology used various approaches to evaluate the phytoplankton community, fish populations, and the potential for toxic algal blooms within the lake. With this data, our team developed a lake management strategy to address both water and nutrient-associated issues.
Great Ecology also developed the Investigation Work Plan, Sampling and Analysis Plan (SAP), Quality Assurance Program Plan (QAPP), and Health and Safety Plan (HASP) associated with the Investigative Order. From 2020-2021, Great Ecology performed extensive watershed modeling to support outside experts with ongoing litigation and identified potential habitat restoration sites within the watershed. Several Great Ecology staff also served as expert witnesses during litigation.

Data Collection Overview

• Regular water quality monitoring data;
• Sediment nutrient flux results;
• Fish, phytoplankton, and zooplankton monitoring;
• Dry and wet weather stormwater data;
• Bathymetric survey results;
• Lake vegetation assessment;
• Upstream biomonitoring data;
• In-lake pilot study efforts to reduce phosphorus via alum and Phoslock application; and
• Annual water level budgets

Conceptual Upstream Restoration Sketch