Stormwater Features

Mechanical separators are used to remove sediment, oils, and large items from stormwater runoff through the use of gravity. Separators store any captured materials and require regularly scheduled maintenance to prevent clogging and overflow.

Property owners with a Mechanical Separator, a completed Inspection Report Form and/or waste manifest form(s) is required to be submitted by the end of each year. Each property owner should have their own Operation & Maintenance Plan for their specific stormwater treatment device and maintenance will vary by unit size and manufacturer. For PDF copies of the Inspection Report form, please email swreports@friscotexas.gov.

Inspection Checklist Verify pipes are always clear and free of debris Inspect structure for damages Determine amount of sediment held at bottom of unit Visually inspect amount of trash floating in unit Verify manhole access is working and lid is in place Schedule service with Vac-Truck Send report to swreports@friscotexas.gov or fill out online form
Common Issues Trash and debris blocking the flow of the pipe Sump is full of sediment and due for service Excessive trash has accumulated on water surface Internal components can be damaged after storm events Unit may have collected hazardous/harmful pollutants

Bioswales are engineered drainageways that are lined with vegetation alongside impervious surfaces like roads and parking lots. Bioswales are designed to allow the collection, filtration, infiltration, and conveyance of stormwater runoff. The added green space provides habitats for wildlife, improves the aesthetics of gray spaces, and helps recharge groundwater.

Inspection checklist Look for erosion where water enters Verify healthy and dense vegetation cover Verify outlet pipes are clear and free of debris Remove trash and litter Remove invasive plants
Common Issues Bare soil within bioswale Missing or dead vegetation Overflow outlet blocked by sediment, debris, or vegetation Ponding water and not draining Erosion within the bioswale Excessive trash and litter Overgrown vegetation

Retention ponds are water bodies that always maintain a permanent pool. This may vary under drought conditions. Detention ponds are water bodies that fill during storms but do not maintain a permanent pool. The buildup of sediment and debris over time will reduce storage capacity and eventually the pond will disappear.

Inspection Checklist Verify inlet and outlets are clear and free of debris Inspect for erosion around infrastructure Verify access is available to inlet and outlet pipes Inspect for erosion at edge of water and slopes Look for excessive sediment, debris or trash within pond Verify healthy vegetation within detention pond Observe color of water and any signs of dead wildlife
Common Issues Erosion along the bank of the pond Overgrown vegetation blocking access to infrastructure Bare soil, missing or dead vegetation within detention pond Excessive trash and leaf litter within pond Fish kill or other water quality impairment Chemical pond dye has been added to water Beaver activity blocking outlet structures

Underground detention systems slowly release stormwater into nearby streams. Systems that are prevented from draining may cause flooding and structure damage. Underground detention systems also allow the use of vertical space when the horizontal space is limited during development.

Inspection checklist Verify detention is draining within 72 hours of rain event Determine level of sediment within pipes Inspect structure for damages Inspect structure for excessive trash or litter Verify manhole is working and lid is in place
Common Issues Outlet blocked by sediment or debris Damages to structure following rain event Sediment build up in pipes disrupting flow Excessive trash and litter accumulation Unknown contaminant captured in structure