Detention basins
Temporarily store runoff and release it at a controlled rate.
Stormwater & Site Drainage
How large roofs, pavement, grading, detention, erosion control, and drainage changes affect runoff and receiving waters.
Understand what the system does, how design choices change impacts, and what records reveal the real operating profile.
System / technology
What it does
Development changes how rainfall moves across a site. Large roofs, parking, roads, compacted soils, grading, and altered drainage patterns can increase runoff volume and peak flow unless mitigated. Construction also creates erosion and sediment risks before permanent controls are established.
Impacts depend on scale, design, operating mode, maintenance, location, and the other systems this technology connects to.
Design matters
Common configurations
The same general system can produce different tradeoffs depending on which configuration is actually proposed.
Retention/infiltration
Stores or infiltrates runoff onsite where soils and regulations allow.
Green infrastructure
Uses vegetated or distributed controls to manage smaller events.
Industrial stormwater controls
Adds source control, treatment, or monitoring for material-handling areas.
Risk pathways
What can matter
Downstream flooding or channel erosion
Construction sediment discharges
Contaminated runoff from industrial areas
Failure or poor maintenance of detention systems
Changes to wetlands, streams, or groundwater recharge
Questions to ask
- ?How much impervious area will be created at full buildout?
- ?Where does runoff go today and after development?
- ?What design storms are modeled?
- ?How are downstream constraints considered?
- ?What erosion controls apply during construction?
- ?Are industrial pollutants exposed to stormwater?
- ?Who maintains detention/treatment systems?
- ?What happens during events larger than the design storm?
Build the record
Evidence to look for
Existing/proposed drainage plan
Hydrologic/hydraulic model
Stormwater pollution prevention plan
Erosion-control plan
Wetland/stream delineation
Detention maintenance agreement
Industrial stormwater permit
Downstream capacity analysis
Where it fits
Related project types & issue guides
Project types
Hyperscale & Large Data Centers
Open →Large computing campuses whose local impacts depend heavily on power, cooling, water, backup systems, siting, and buildout assumptions.
Battery Energy Storage Facilities
Open →Grid-scale battery systems used for energy shifting, capacity, reliability, renewable integration, or other electric-system services.
Large Industrial Campuses
Open →Multi-building or phased industrial developments whose cumulative infrastructure, land-use, and community effects can exceed those of any single facility.
Logistics & Warehouse Campuses
Open →Large distribution, fulfillment, freight, and warehousing developments where traffic, land coverage, lighting, labor, and transportation infrastructure dominate the local impact profile.
Issue guides
Environment & Natural Resources
Open →Understanding how land disturbance, emissions, water, habitat, waste, fuel supply, and cumulative effects interact with a place.
Water & Cooling
Open →Understanding water demand, cooling technology, wastewater, infrastructure, and the conditions that determine real-world impacts.
Land Use & Zoning
Open →Understanding where a project can be built, how the site fits surrounding uses, and what public approvals or land-use changes are required.
Infrastructure & Traffic
Open →Understanding project-driven demands on roads, freight routes, utilities, emergency access, public works, and other shared infrastructure.
Supporting detail
Evaluation cautions & current applications
Evaluation cautions3 cautions
- !Check full-buildout impervious area rather than first-phase acreage.
- !Peak-flow compliance alone may not address runoff volume, water quality, or downstream erosion.
- !Construction-phase drainage can create impacts before permanent basins are operational.