Our team of experts are central to water resources issues, including advanced water treatment for beneficial use; dam relicensing and dam safety; fluvial geomorphology and sediment transport analyses; stormwater permitting, treatment and compliance; groundwater quality, quantity, and cleanup; and invasive species eradication and control.

Water resources is of vital importance to the western USA, and continues to grow in importance worldwide. Catalyst has worked locally to globally in this market space.  We provide expert CEQA/NEPA services to the City of Los Angeles as they implement their visionary enhanced watershed management plan, and to help achieve the bold goal of recycling 100% of their wastewater by 2035.

We have worked for numerous California water agencies and districts as they balance the need for the resource against the requirements of the state, region, and other biological resource agencies. We have led environmental reviews of some of the major water resource issues facing California, including work on the Klamath River mitigating the effects of dams on salmon stocks and Native American cultural practices, and the host of issues surrounding water rights and water quality concerns in the Sacramento Delta.

We have addressed water treatment to beneficially reuse brackish water in California, the USA, Australia, Ecuador, and Colombia.  

Catalyst’s geologists and engineers conduct geomorphological and fluvial analyses including annual monitoring to evaluate potential changes in the river systems related to land use. This work has included hydroelectric and other dams across the mountains of California in the jurisdiction of the USFS, NPS, and BLM as well as local agencies.  We have analyzed environmental effects of dam safety retrofits, development and implementation of sediment management plans, and long term monitoring and restoration of aquatic habitat affected by natural (fire, landslide) and human-induced causes.

We prepare stormwater sampling programs in compliance with complex Industrial NPDES permits and conduct stormwater sampling, analysis and reporting. We work with our clients to identify solutions to discharge of known contaminants through best Management Practices. Our team also develops and implements large scale groundwater monitoring programs. We provide permitting and compliance solutions to our clients with regard to water resources including development of permit packages for 404 permits, 401 Water Quality certifications, Waste Discharge Reports and Streambed Alteration Agreements, coordination with federal, state, and local regulatory agencies, assistance with project design to minimize impacts, and potential design mitigation projects, as needed.

Catalyst conducted resource studies to support a proposed development project in the Santa Clara River Watershed and prepare the surface water hydrology/flood control, geomorphology/riparian resources, and hazards sections of the Resources Management and Development Plan /Spineflower Conservation Plan (RMDP/SCP) EIR/EIS
Catalyst staff conducted numerous sediment transport studies in support of Southern California Edison Company’s Kern River No. 1 and No. 3 Hydroelectric Projects in California including ongoing instream monitoring


Environmental planning and permittings
CEQA/Other State-Equivalent NEPA Programs
Economic Analysis
Mitigation Planning
Endangered Species Act Consultation
Local and Regional Agency Coordination and Approvals
Constraints analyses
Strategic Regulatory Analysis
Technical Advisory Roles
Expert Testimony
Litigation Support
Underground Injection Control Strategy, Aquifer Exemptions
Expert Services
FERC Dam Security Assessments
Hydroelectric Relicensing and Decommissioning
CDFW 1600 Streambed Alteration Agreements
NPDES Permitting, Sampling/Monitoring and Reporting
Waste Discharge Reports
316a and 316b Impingement and Entrainment Permitting
Clean Water Act Permitting: 404 Permits, 401 Water Quality Certifications
Field services
Site Delineation and Characterization
Remedial Action Plans
Feasibility Studies and Constraints Analysis
Phase 2 Environmental Site Assessments
Laboratory Data Validation and Quality Analysis
Stormwater and Surface water Sampling Programs
Sediment Transport Analysis
Geomorphic Analysis
Groundwater Monitoring Programs
Agency Coordination and Reporting
Phase 1 and 2 Environmental Site Assessments
Laboratory Data Validation and Quality Analysis
Soil Sampling
Constraints Analyses
Strategic Regulatory Analysis
Technical Advisory Roles
Expert Testimony
Litigation Support

Water projects

Water experts in our team

Water related news & insights


Recycled Water


Invasive Species


Dam Safety


LA Enhanced Water Management Plan