Timmons Group’s stormwater services team, housed in our infrastructure group, consists of more than a dozen highly specialized staff with extensive experience in stormwater management and public drainage solutions for local governments. Our engineers with backgrounds in civil engineering, water resources, biological systems engineering, and ecological restoration dedicate their professional careers to solving complex drainage problems and creating sustainable solutions for stormwater management.

Whether providing independent tasks for stormwater on-call contracts, or supporting services for public land or infrastructure projects, our staff is familiar with the unique complexities of public sector projects. We have completed hundreds of stormwater improvement projects and emergency repairs on degraded and undersized existing infrastructure, as well as TMDL-driven retrofit and stream restoration projects. We are familiar with county infrastructure and capital project drivers, including the regulatory framework that pertains to stormwater management in the Commonwealth of Virginia, such as the Virginia Stormwater Management Program (VSMP), the Virginia Pollutant Discharge Elimination System (VPDES), and Impounding Structure regulations. We can provide comprehensive project services from initial data collection (such as survey, utility location, and wetland delineation), through engineering analysis and design, construction, and post-construction inspection and monitoring services. We are also capable of providing watershed and/or County-scale analyses, including floodplain and dam safety services. Our primary objective is to serve as an extension of your staff to meet the needs of the County of Prince George’s constituents.

Stormwater Management & Public Drainage Services

Analysis & Design
• Inventory and Data Collection
• GIS mapping, analyses, and editing
• Watershed Delineation
• Hydrologic & Hydraulic Modeling (2D, SWMM, etc.)
• Drainage Improvement Design
• Water Quality Retrofit Solutions
• Green Infrastructure Engineering and Design
• Easements and Property Acquisition Services
• Construction Cost Estimates, Technical Specifications, Bidding Assistance
• Construction Administration
• Construction Materials Testing

Floodplain Management
• Floodplain Studies
• Mapping & Analysis
• FEMA Assistance
• NFIP and CRS Assistance

Stormwater Regulatory Compliance & Support
• VSMP and MS4 Program Development and Planning
• Ordinance Development and Council/Board Liaison Services
• Policies and Procedures
• Plan Review and Inspection Services
• Data Management
• Public Outreach and Education
• TMDL Action Planning and Compliance Strategies

Dam Safety & Impounding Structures
• Inspections & Reports
• Dam Failure Analyses & Inundation Studies
• Emergency Action Planning

Ecological Restoration
• Stream & Wetland Restoration
• Living Shorelines
• Bluff Stabilization


Apple Branch Watershed Study FEMA Advanced Fund Grant
Town of Wake Forest Flood Study Reviews On-Call Contract
Raleigh Stormwater On-Call Drainage Assistance Program
Town of Cary Stormwater On-Call Contract
Wooten Meadow Park
Quarter Mill Stream Restoration
Virginia Home for Boys and Girls Stream Restoration
Cedar Creek – Reach 2 & 5 Stream Restoration
Birchett Estates Stream Restoration
Reedy Creek Mitigation Bank
Mist Lake Water Management Complex Bridge Design
Mulberry Run BMP Retrofit