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Wetlands and Waters Assessment
and Delineation

If your project will or potentially will affect wetlands or waters (aquatic resources) within and around the project site, you need to have a Wetlands and Waters Assessment and Delineation Study (also known as Aquatic Resources Delineation) to ensure your project complies with all applicable laws and regulations. 

The purpose of these assessments is to identify the presence and approximate extent (acreage) of Waters of the United States (regulated by the U.S. Army Corps of Engineers), and Waters of the State (regulated by the Regional Water Quality Control Boards and the California Department of Fish and Wildlife). The results of the assessment and delineation are used to determine impacts, permit processes, and develop mitigation plans.

What is a Wetland or Aquatic Resource?

Many people believe that the term “wetlands” refers to clearly visible bodies of water like streams, rivers, ponds, lakes, bogs, or marshes. But in reality, many areas and portions of habitats are considered aquatic resources, including seasonal pools, ephemeral drainage, streams, creeks, marshes, rivers, and swales — even if some of them are dry for most of the year. During the Wetlands and Waters Assessment, our staff determines the dominance of wetland plant species and the presence of hydric soil and wetland hydrologic indicators.
Wetlands and Waters Assessment and Delineation Study: Wetland delineation being conducted at the Salton Sea in Southern California
Wetland delineation conducted at the Salton Sea in Southern California.
Wetlands and Waters Assessment and Delineation Study: Vernal pool complex, a wetland habitat in Northern California
Vernal pool complex, a wetland habitat in Northern California.

Northern and Southern California - Distinct Habitat Differences under Identical Regulations

Northern and Southern California habitats differ significantly, but both are subject to the same State and Federal regulations. Due to Southern California’s arid conditions, its wetlands and waters are often ephemeral in nature, meaning they may not be obvious year-round. Northern California’s habitat supports a much larger number of persistent wetlands and waters.

Wetlands and Waters Assessment and Delineation

ECORP has extensive experience conducting Wetlands and Waters Assessments and Aquatic Resource Delineations throughout California and adjacent states. Our team is experienced with a broad range of freshwater and coastal wetlands. With our experience, in-depth knowledge of all applicable regulations, and professional relations with regulatory agencies, we can assure a complete and legally defensible report.

Wetlands and Waters Assessment and Delineation Study: Senior, staff, and associate biologists conducting reconnaissance survey at the Salton Sea, California.
Senior Biologist Jeff Tupen, Staff Biologist Daniel Wong, and Associate Biologist Christina Torres conducting reconnaissance survey located at the Salton Sea, California.

Our field investigations collect site-specific data, including soil characteristics (hydric), assessment of plant species composition, and evaluation of hydrologic conditions. This information is the basis for determining the presence of a wetland.

Aquatic Resource Delineations are completed using our GPS and GIS mapping services to create the most detailed maps of the wetland and the locations of identified species. Upon completion, the assessment is submitted to the appropriate agencies for concurrence.

Other Wetlands and Waters Services Provided by ECORP

The services include:
  • Project assessment/due diligence analysis
  • Aquatic Resource Delineation
  • U.S. Army Corps of Engineers (USACE) Section 404 permitting, including Nationwide Permits, Letter of Permissions, and Individual Permits
  • Regional Water Quality Control Boards (RWQCB) Section 401 certification, including Porter-Cologne Act
  • California Department of Fish and Wildlife (CDFW) Section 1602 streambed alteration agreements
  • 404(b)(1) Alternative Analysis
  • Aquatic, riparian, and estuarine habitat restoration
  • Mitigation planning and design
  • Alternatives analyses
  • Watershed and ecosystem restoration planning
Wetlands and Waters Assessment and Delineation Study: ECORP staff Biologist conducting vernal pool fairy shrimp sampling during the wet season
ECORP staff Biologist conducting vernal pool fairy shrimp sampling during the wet season.

Other services, including Unmanned Aerial Services (UAS) which provide more accurate site mapping, may be necessary or useful as the study progresses. Those will be identified and approved by your team before they are implemented.

Choose ECORP for Wetlands and Waters Assessment and Delineation Services

Our combination of exceptional staff, in-depth knowledge of regulations and processes, and professional working relationships with Federal and State regulatory agencies is hard to match. When you use our services, you can be sure all your project permitting and compliance requirements will be identified, allowing you to proceed with confidence. Contact ECORP today to discuss your project and learn more about our Wetlands and Waters Assessment and Delineation Study Services.

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