Stormwater Utility Program

What is a stormwater system?

During a rainfall event, some of the water soaks into the soil, but a portion of the water is unable to be absorbed by the ground. This portion of water that falls as rain but runs off the land at the surface is referred to as "stormwater". A stormwater or "drainage" system is the combination of natural and constructed facilities that collect, contain, and provide for the flow of this surface water from the land to a receiving water body. A typical drainage system consists of both natural and man-made features, including pipes, inlets, culverts, street gutters, ditches, channels, creeks, lakes, ponds, dams, tunnels, and floodwalls. Stormwater systems are important because they prevent or mitigate undesirable conditions such as flooding, erosion, and pollution of water bodies.

What are some typical improvements to stormwater systems?

Improvement projects for stormwater systems vary greatly in size and expense. Sometimes, fixing a drainage problem may be as simple as regularly mowing the roadside ditch, or it may require an expensive and disruptive project, such as upsizing the underground stormwater pipes through an entire subdivision. Preventative maintenance can increase the useful life of such large-scale projects.

How are these projects funded?

One way that many cities have begun to finance the increasing cost of stormwater management programs is by developing and implementing a separate Storm Water Utility (SWU) Fund. A Storm Water Utility Fund can be implemented by a city to pay for programs that prevent, mitigate, and correct problems with the existing stormwater system. The City of Sherman recently established a SWU, which will serve as a stable financing mechanism for the City's stormwater management program.

Storm Water Utility (SWU) Enactment

 A SWU is required by State law to be enacted by ordinance through a majority vote of the City Council. The implementation ordinance declares the utility adoption and declares the stormwater system of the City to be a public utility. The resolution sets the schedule of stormwater charges. The SWU was adopted on September 18, 2017 by City Ordinance 6057 and 6058.

City Ordinance No. 6057 

City Ordinance No. 6058

How will the SWU fees be calculated and collected?

Each developed property will pay a fee that is directly related to the property’s impact to the City’s stormwater collection system. This impact can be represented by the property’s impervious area. Impervious areas (hard surfaces) do not allow stormwater to infiltrate into the soil and result in increased runoff to the stormwater collection system. Thus, the SWU rates are based on the amount of impervious area for each property. Typical impervious areas include rooftops, driveways, and parking lots.

The most common method to collect SWU charges is through the water utility bill, which is the method Sherman has employed. The fee has been added as a single line item on your monthly water utility bill.

How much will I pay?

Single-family residential properties are divided into three (3) tiers based on their impervious area. Most Single-family residential properties fall within Tier 2, those with smaller impervious area fall within Tier 1, and those with the greatest amount of impervious area fall within Tier 3. Properties will pay a monthly SWU fee according to their tier classification:

Tier 1 = $0.60, Tier 2 = $1.00, Tier 3 = $1.80.

Non-residential properties (commercial, multi-family, churches, etc.) are assessed a fee based on their equivalent residential unit (ERU). For the City of Sherman, one (1) ERU was determined to be 3,400 square feet, which is the average impervious area for residential properties in the city. Each non-residential property will pay a monthly SWU of $1.00 per total number of ERUs. For example, a commercial property like a fast food chain restaurant with 7 ERU (23,800 sq ft of impervious area), will pay a SWU fee of $7 per month.


Property Type
Impervious Area (sq. ft.)
Monthly Drainage Utility Fee
Single-family residential


Tier 1
<2,400
$0.60
Tier 2
2,400-4,600
$1.00
Tier 3
>4,600
$1.80
All other nonexempt property

$1.00 per ERU*

*ERU (equivalent residential unit) = 3,400 square feet impervious area

For specific questions about your property, please contact the Engineering Department at 903-892-7208.

City Ordinance No. 6057

City Ordinance No. 6058