Project Manager – Stormwater and Water Resources

Costa Mesa, CAFull-time$112k–$146kPosted Jul 16, 2026

Overview

Do you want to build an impactful career to change the world for the better? 

Geosyntec has an exciting opportunity for a Project Manager – Stormwater and Water Resources based in our Costa Mesa, California office. This role will lead and contribute to public- and private-sector projects involving stormwater and non-stormwater regulatory compliance, Water Quality Management Plans (WQMPs), Best Management Practice (BMP) planning and design, Low Impact Development (LID) strategies, hydrologic and hydrogeologic evaluations, and Clean Water Act/NPDES regulatory support.

Geosyntec is an innovative, international engineering and consulting firm serving private and public-sector clients to address new ventures and complex problems involving our environment, natural resources, and civil infrastructure. Our engineers, scientists, technical and project employees serve our clients from offices across the world. Our clients ask us to address their new ventures and most challenging problems involving the environment, natural resources, and civil infrastructure. Ranked by ENR as one of the top environmental engineering design firms, Geosyntec is internationally known for its technical leadership, broad experience, and exceptional client service.

We invest in our people. Each employee is unique, and your career at Geosyntec will be too. We offer competitive pay and benefits, and well-being programs to support you and your family.

To Learn More Visit: http://www.geosyntec.com/careers/.

Essential Duties and Responsibilities

Manage and support stormwater/MS4 permit compliance, water quality planning, and BMP design projects for municipal, public agency, developer, and private-sector clients, with emphasis on Orange County and Southern California regulatory programs.
Provide technical and regulatory support for NPDES/MS4 permit compliance, municipal stormwater program implementation, industrial/commercial inspection programs, annual reporting, program effectiveness assessments, and construction stormwater compliance.
Prepare, review, and implement Water Quality Management Plans (WQMPs), Stormwater Management Plans (SWMPs), Stormwater Pollution Prevention Plans (SWPPPs), stormwater compliance plans, hydromodification analyses, runoff calculations, and related regulatory submittals.
Lead or support the planning, siting, sizing, and design of site design, source control, treatment control, infiltration, and drywell BMPs consistent with Orange County BMP Design Manual requirements, local implementation plans, and applicable regional MS4 permit criteria.
Evaluate site-specific hydrologic and hydrogeologic conditions to support stormwater capture, infiltration feasibility, drywell sizing, water quality treatment, and drainage design decisions.
Develop and review stormwater and civil design components, including LID features, infiltration BMPs, drywell systems, bioretention systems, permeable pavement, detention/retention facilities, grading concepts, drainage improvements, and erosion and sediment control measures.
Apply hydrologic and hydraulic modeling, drainage calculations, water quality sizing methods, and design documentation using tools such as Civil 3D, ArcGIS, HydroCalc, EPA SWMM, HEC-RAS, and related platforms.
Support plan check, permit coordination, and agency consultation with municipalities, Orange County agencies, Regional Water Quality Control Boards, public works departments, and other regulatory stakeholders.
Conduct and coordinate site visits, stormwater inspections, industrial/commercial facility inspections, BMP condition assessments, construction-phase observations, and other field-based activities, as needed.
Prepare technical memoranda, water quality plans, engineering calculations, design reports, figures, specifications, cost estimates, permit support materials, and client-ready deliverables.
Coordinate technical deliverables with CAD/GIS staff, including plan exhibits, water quality inventories, maps, and design support materials.
Manage project scope, schedule, budget, quality, and client communications for multiple concurrent assignments in a consulting environment.
Build and maintain strong relationships with municipal staff, agency representatives, engineers, architects, developers, contractors, and internal Geosyntec colleagues.
Mentor junior staff, review technical work products, provide training and QA/QC oversight, and contribute to multidisciplinary project delivery.
Support business development, proposal preparation, public-sector client engagement, client relationship management, and other contributions consistent with Geosyntec’s sell-manage-do business model.
Drive personal, company, and rental vehicles to client or company project or office sites and other business locations, as needed.

Education and Licensure

Bachelor’s degree in environmental studies, environmental science, civil engineering, environmental engineering, water resources, or a closely related discipline with emphasis on stormwater, water quality, drainage, municipal infrastructure, planning, or regulatory compliance. (required)
Master’s degree in environmental science, water resources management, environmental management, civil engineering, environmental engineering, or a related discipline. (preferred)
Professional registration (i.e., P.E.) in California or demonstrated progress toward California registration, with ability to obtain registration within 12 months of employment. (preferred)
Stormwater-related certifications such as QSP/QSD, CPSWQ, or similar credentials. (preferred)

Skills, Experience and Qualifications

At least 7 years of related experience in stormwater, water resources, environmental consulting, municipal compliance, BMP design, or related technical consulting, including experience managing projects, budgets, staff, or client relationships; or equivalent combination of education and experience. (required)
Demonstrated experience supporting Phase I and Phase II MS4 permit compliance, NPDES stormwater programs, municipal stormwater implementation, WQMP/SWMP/SWPPP preparation, annual reporting, performance assessments, and inspection programs. (required)
Strong working knowledge of Southern California and Orange County stormwater requirements, including OC-specific BMP design expectations, WQMP requirements, local implementation plans, regional MS4 permit compliance considerations, and California stormwater regulatory programs. (required)
Experience planning, sizing, designing, and reviewing stormwater BMPs, LID features, infiltration systems, drywell systems, drainage improvements, treatment control systems, and related civil/site design components. (required)
Experience evaluating hydrologic and hydrogeologic impacts related to stormwater capture, infiltration, drywell feasibility, BMP performance, and water quality treatment design. (preferred)
Experience preparing or reviewing engineering calculations, runoff calculations, drainage studies, hydrologic and hydraulic analyses, design exhibits, technical reports, specifications, regulatory correspondence, and permit support documents. (required)
Experience with design, analysis, and mapping tools such as Civil 3D, ArcGIS, HydroCalc, EPA SWMM, HEC-RAS, R, Microsoft Excel, or similar platforms. (preferred)
Ability and willingness to support field work, including municipal, industrial, and commercial inspections; BMP assessments; stormwater monitoring support; construction observation; and client or agency site visits. (required)
Strong project management skills, including scope, schedule, budget, QA/QC, client coordination, team leadership, technical training, and delivery of multiple concurrent assignments. (required)
Client-facing communication and business development experience with engineers, architects, developers, contractors, municipalities, public agencies, and regulatory stakeholders. (preferred)
Excellent written, verbal, organizational, and interpersonal communication skills, with the ability to prepare client, agency, and public-facing deliverables. (required)
Health & Safety training, medical monitoring, and client-driven drug and background testing may be required.
Valid U.S. driver’s license and a satisfactory driving record for business travel. (required)

This opportunity will be posted for at least five days. Below are the potential compensation ranges that we in good faith believe are applicable for this role at the time of this posting and are only applicable for jobs to be performed in the specified location(s) below. The typical base salary range for this position is just one component of Geosyntec’s total compensation package for employees. Actual compensation will be determined based on education, experience, skill set and location.

Minimum Salary: $112,260/year / Maximum Salary: $145,940/year (Costa Mesa)

We offer a comprehensive benefits package including paid holidays, vacation, sick, and personal paid time off, medical, dental, vision, life, and disability insurance, 401(k), and other benefits to eligible employees.

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