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Funding from the UNC Stormwater Utility comes from 3 sources, in descending order:

  • Stormwater Utility – Established in fiscal year 2014, the stormwater utility bills all University customers based on their impervious area. This budget funds maintenance staff and repair/improvement projects. Learn more about the utility below.
  • Mark-up on Water/Wastewater Bills – A five percent mark-up on all University water/sewer bills provides funding for several positions, including three staff in Energy Services and EHS who are focused on stormwater.
  • EHS Budget – The EHS budget funds one position that works on stormwater and provides funding for education and outreach activities.

Stormwater Utility Information

Items Paid for by the Stormwater Utility Fee

What is paid for by the stormwater utility fee?

  • Preventive maintenance of the storm drain system, specifically, the annual clean-out of all the inlets and manholes on campus.
  • Preventive maintenance of stormwater control measures (SCMs), specifically the annual or quarterly inspection and clean-out required by stormwater regulations. Includes permeable pavement, ponds, wetlands, bioretention, and underground storage and water quality devices.
  • Minor repairs to stormwater infrastructure (pipes, inlets, manholes, SCMs).
  • Street sweeping.
  • Identified deferred maintenance projects costing less than $200,000 per project.
  • Predictive repair and replacement of aging stormwater infrastructure (as funding allows).
  • Specialized equipment needed to perform the stormwater-specific work.
  • Technical assistance by University staff regarding drainage and stormwater.

Who does the work?

The University’s Grounds Services department stormwater crew does the preventive maintenance of the stormwater infrastructure and the street sweeping.  Energy Services engineers provide design Other work is done by Facilities Services when feasible.  Some projects require design and construction by outside contractors.

What work is not paid for by the stormwater utility fee?

  • Construction of new stormwater BMPs as required with a new or redevelopment project.  The capital costs for design and construction will be covered by the project.  After construction is complete, the stormwater utility fee will cover the on-going maintenance.
  • Routine landscape maintenance, including the routine landscape maintenance (e.g. mowing, weeding, pruning, mulching, litter removal, irrigation) of stormwater control BMPs such as bioretention and green roofs that require attention more frequently than quarterly.  Less frequent maintenance is included (e.g. removing cattails from a pond, removing trees from a dam, or rebuilding a BMP at the end of its life-cycle).
  • Building drainage systems including gutters, downspouts, roof drains, window well drains, stairwell drains, trench drains at doorways, foundation drains, well points, sump pumps, and any pipes inside or under the building.  The division line between the building’s responsibility and Energy Services’ responsibility is the first stormwater inlet or manhole.  Cleanouts are not considered inlets or manholes.
  • Flooding interior to a building.  However, if the source of the flooding appears to be from the runoff exterior to the building, Energy Services staff will collaborate with staff from other departments to determine the cause and remedy.

Impervious Area – Basis for Billing

What is the basis for billing customers?
Impervious area is the basis of the bills, because it isn’t feasible to meter stormwater.  Impervious area includes roofs, sidewalks, plazas, roads, driveways, and parking lots – any surface that doesn’t let water infiltrate into the ground.  The impervious area is billed in units of one thousand square feet (ksf).
Why is impervious area used?
Impervious area is a good proxy for the amount of stormwater services utilized.  Impervious area creates significantly more runoff and downstream water quality impacts than pervious area.  Pipes and channels are needed to carry the runoff.  SCMs control flooding and water quality.
How is the impervious area calculated?
The University GIS mapping system contains shapes (polygons) representing the impervious area on campus.  This mapping is based on surveys, site plans, and aerial photography.  The mapping is updated regularly by GIS/mapping staff in the Facilities Technology Group and Energy Services. Each year, a snapshot of the mapping data is used to calculate the impervious area.
How was impervious area assigned to customers?
Buildings and other areas with current utility services through Energy Services were assigned to the current customer. Areas without current utility service were addressed individually.
How often is impervious area calculated?
The same units of impervious area are used for each month in the fiscal year.  Impervious area is updated for each fiscal year.
What land cover surfaces are considered impervious area?
The following are considered impervious area:

  • Building roofs, including buildings under construction
  • Parking lots*
  • Roads, driveways, and service roads*
  • Sidewalks and plazas*
  • Service areas and other areas used by vehicles *
  • Recreation surfaces (synthetic turf fields, basketball and tennis courts, tracks, swimming pools)
  • Miscellaneous areas such as walls, steps, and concrete pads*

*Includes gravel, Chapel Hill gravel, compacted dirt, and permeable pavement.

Billing and Rates

Who does the billing?
Energy Services bills customers for stormwater on a monthly basis.
How are the rates calculated?
The stormwater rate is developed by dividing the annual stormwater budget by the total impervious area on campus.  Since customers are billed monthly, the rate is converted to dollars per one thousand square feet of impervious per month ($/ksf/month).
If a capital project builds a Stormwater Control Measure (SCM), does that site still have to pay the stormwater fee?
Yes.  Sites with all types of SCMs are still responsible for paying the stormwater fee.  The budget is used for the maintenance of the SCMs and the storm drain system.  Capital projects pay to build SCMs but not to maintain them.  These maintenance needs are increased when SCMs are added.
What is done in other places to pay for stormwater?
Impervious area based stormwater utility fees are the most common source of dedicated stormwater funding.  The fees are often billed using existing collection systems such as tax bills or water bills.
If a customer believes their bill is incorrect, what do they do?
Please contact Sally Hoyt at 919-843-880 or Ben Poulson at 919-843-8308.