What is stormwater and why do we need to manage it?
Stormwater is urban runoff that is a direct result of precipitation that cannot infiltrate into the soil or be absorbed by vegetation. It flows through pipes, gutters, swales, or over land. It washes pollutants such as soil, trash, automotive fluids, fertilizers, and detergents into our creeks, rivers, and lakes. In heavy storms, it can cause flash flooding drainage problems.
Urbanization causes significant changes in runoff characteristics. Such changes can:
- increase erosion and formation of gullies in upland areas,
- increase in-stream scour and erosion,
- increase sediment deposition in lower areas,
- degrade water quality,
- result in more and faster runoff and more frequent flooding,
- reduce groundwater recharge, lower the water table, and result in streams drying up more frequently, and
- result in negative effects on stream ecological communities.
These impacts can impact both the built environment and natural systems, and require continuous management, maintenance, repair and replacement of the stormwater management system, and careful planning to mitigate existing and future problems.
How does the Town's stormwater related efforts benefit taxpayers, homeowners, and other community members?
The following are some of the primary services and activities:
- water quality improvement activities (regulatory and local needs based)
- stream and riparian restoration and other beneficial projects
- public drainage and storm sewer maintenance, repair, and improvement
- street sweeping and cleaning
- National Flood Insurance Program (NFIP) participation
- supporting eligible residents interested in pursuing flood mitigation grants
- pursuing and administering grants for public projects
- watershed plans and other studies
- public education and participation
- Land Use Ordinance administration
What state and federal requirements does the Town have to meet with regard to water resource issues?
The Town participates in the National Flood Insurance Program that requires administration of the federal regulations pertaining to floodplain management and other flooding related issues.
The Town administers it National Pollutant Discharge Elimination System - Phase 2 stormwater permit and annually reports to the NC Department of Environmental Quality. This permit requires the Town to meet the measures outlined in the permit to reduce and mitigate non-point source stormwater pollution
The Town administers the state's Water Supply Watershed, Jordan Lake Rules, and Stormwater Minimum Design Criteria development regulations.
The Town ensures that state and federal jurisdictional waters and wetlands are not impacted without proper certification from the Army Corps of Engineers and the state's Wetlands Certification Unit.
What is an impervious surface?
In general terms, an impervious surface is a hardened surface (concrete, rooftop, asphalt, compacted gravel, etc.) that does not allow rainfall to infiltrate. Increases in impervious surface areas, if not treated by a Stormwater Control Measure, cause increased pollutant loading, volume and rate of stormwater runoff, decreased infiltration of stormwater into the soil, and a lower stream base flow and groundwater table.
The streambank on my property is eroding. What can I do?
If your streambank is lined with a natural buffer of trees or shrubs, keep them in place as they are stabilizing the soil, filtering pollutants, and creating beneficial habitat. Cutting this vegetation back or mowing right up to the streambank could compromise these benefits. The NC State Cooperative Extension provides some guidance on how to reinforce streambanks here. Please check with staff (Planning or Stormwater) before doing any more extensive work within a stream channel or buffer.