Stormwater Information

Department of Public Works

About Sterling's Stormwater Management Plan

Under the National Pollutant Discharge Elimination System (NPDES) stormwater program, operators of regulated small municipal separate storm sewer systems (MS4s) require authorization to discharge stormwater under an NPDES permit. The Town of Sterling, located within an Urbanized Area as identified by the latest Decennial (2000) census and designated as a partially regulated community, applied for coverage under NPDES General Permit for Stormwater Discharges. In order to obtain permit coverage, the Town was required to develop a stormwater management program (SWMP) designed to reduce the discharge of pollutants from Sterling’s MS4 to the maximum extent practicable; protect water quality, and satisfy the water quality requirements of the Clean Water Act and Massachusetts Water Quality Standards. The SWMP includes six minimum control measures. The minimum control measures are as follows:

  1. Public Education and Outreach
  2. Public Involvement and Participation
  3. Illicit Discharge Detection and Elimination
  4. Construction Site Stormwater Runoff Control
  5. Post Construction Stormwater Management in New Construction and Redevelopment
  6. Pollution Prevention and Good Housekeeping in Municipal Operations

In order to apply for coverage under a General Permit, the Town had to submit a Notice of Intent to the U.S Environmental Protection Agency (EPA) and the Massachusetts Department of Environmental Protection (DEP). The NOI provided information pertaining to the permit applicant, including the applicant’s eligibility for a General Permit and a listing all receiving waters within the community. In addition, the NOI provided a summary of, and implementation schedule for, the Town’s SWMP.

Prior to submitting a NOI the Town had to confirm that it was eligible for coverage under the General Permit by establishing that discharges from its storm drain system do not adversely impact endangered species, critical habitat and historic properties. In addition, the Town had to perform research to identify all of its receiving waters and identify those that have been classified as Water Quality Impaired Waters by the MA DEP. The following sections briefly summarize the results of research performed to assess the Town’s eligibility and investigations conducted to document the status of the Town’s impaired waters. They are only a part of it's Stormwater Management plan. If you would like to review a copy of the Plan please contact us.

Eligibility Criteria

The Town of Sterling is in compliance with the National Historic Preservation Act (NHPA) eligibility criteria for the NPDES General Permit for Stormwater Discharges from Small MS4s. In order to make this determination, the Town produced a map that delineated all known stormwater outfalls and the State Register of Historic Places Datalayers within the Town’s municipal boundaries. The Historic Places Datalayers were downloaded from MassGIS in May 2003 and include National Register Districts, National Historic Landmarks, National Register Individual Properties, and Preservation Restrictions. There are no historic properties identified in the path of Sterling’s MS4 stormwater discharges or allowable non-stormwater discharges and the Town does not propose the construction of any structural BMPs for coverage under this permit. Because there were no historical sites eligible for listing on the National Register included in the datalayer, the Town requested confirmation from the Massachusetts Historical Commission (MHC) that the outfalls identified on the Outfall Location Map did not impact any historical sites eligible for listing. The Town also requested that MHC verify that all sites currently listed on the National Register had been identified on the Town’s map. A letter received from the MHC confirming this information has been included in Attachment C.

Discharges to Water Quality Impaired Waters

According to the Massachusetts Year 2002 Integrated List of Waters, there is only one waterbody within the Town of Sterling identified as an impaired water requiring Total Maximum Daily Load (TMDL) limits.  This waterbody does not receive any direct discharges from the regulated municipal storm drainage system and therefore has not been identified in Section C of the NOI.  The attached table lists this waterbody, its state identification number, surface area, and pollutant of concern.  Because this document is currently in draft form, Arthur Johnson of the Massachusetts Department of Environmental Protection (DEP) was contacted to verify this information.  Confirmation that this waterbody would maintain its current designation was received in the form of an electronic email on July 15, 2003.  

Sterling Category 5 - Waters Requiring A TMDL

Name   Segment I.D. Size Pollutant of Concern
East Brook Wachusett MA81-30_2002 5.4 Miles Pathogens

The overall goal of the Town’s SWMP is to reduce the discharge of pollutants from the storm drainage system to all receiving waters, including any listed as impaired in the Massachusetts Year 2002 Integrated List of Waters. The following sections briefly summarize how the various components of the Town’s SWMP will improve the quality of stormwater discharged to the receiving waters.

The Town’s planned public education efforts and public participation activities will raise awareness throughout the community regarding the impacts of non-point source pollution on the receiving waterbodies and will educate the public on methods to reduce this type of pollution. It is expected that as the public becomes more aware of the Community’s water quality issues and the responsibilities expected of them and others in the Community, they will modify their behaviors to help improve water quality of all receiving waters.

Meeting the requirements of the Illicit Discharge Detection and Elimination minimum control measure will enable the Town in eliminating any illicit discharges to the storm drainage system. Such untreated discharges contribute high levels of pollutants, including heavy metals, toxics, oil and grease, solvents, nutrients, viruses, and bacteria to receiving waterbodies thereby degrading water quality and threatening the health of aquatic wildlife.

Because polluted stormwater runoff from construction sites often includes sediments, solids and sanitary wastes, phosphorous, nitrogen, pesticides, oil and grease, and construction debris it can become a serious contributor of pollutants to the Town’s impaired waters. The BMPs proposed to meet the Construction Site Stormwater Runoff minimum control measure will assist in controlling this type of polluted runoff to all waters, with special attention being directed to the Town’s impaired water and other areas of environmental concern.

Similarly, stormwater runoff flowing over areas altered by development can also pick up harmful sediment and chemicals such as oil and grease, pesticides, heavy metals, and nutrients and deposit them to Sterling’s receiving waters. The increased impervious surface that results from new developments in the community also interrupts the natural cycle of water so that it no longer gradually infiltrates through vegetation and soil but instead increases the quantity of water that is delivered to the receiving waters during a storm event. The proposed BMPs for the Post-Construction Stormwater Management in New Development and Redevelopment minimum control measure will assist the Town in controlling both the quality and quantity of stormwater runoff from these new developments. The Town will closely review new development and redevelopment projects that propose to discharge stormwater runoff to the Town’s impaired waters, or other areas of environmental concern, and mitigate the potential for an increase in the pollutants of concern.

The goal of the Pollution Prevention and Good Housekeeping for Municipal Operations minimum control measure is to improve and protect the quality of receiving waters by improving the performance of municipal operations and DPW facility management. Proposed BMPs such as formalizing the street sweeping and catch basin cleaning programs and conducting a DPW employee training program will assist in reducing the type of pollutants that collect on streets, parking lots, and DPW storage and vehicle maintenance areas.

Total Maximum Daily Load Allocations

The MADEP is responsible under Massachusetts General Law (MGL) Chapter 21 for monitoring the State’s waters, identifying those waters that are impaired, and developing a plan to bring them back into compliance with the Massachusetts Surface Water Quality Standards.  Once a waterbody is identified as impaired, the DEP is required by the Federal Clean Water Act to develop a Total Maximum Daily Load (TMDL) for the impaired waterbody.  The process of developing a TMDL includes identifying the causes and source(s) of the pollutant from direct discharges and indirect discharges, determining the maximum amount of the pollutant that can be discharged to the impaired waterbody to meet water quality standards, and developing the plan to meet that goal.  As mentioned in the previous section, the Massachusetts Year 2002 Integrated List of Waters identified one waterbody within Sterling’s municipal boundaries as impaired water requiring a TMDL.  Currently there is no approved TMDL for East Wachusett Brook and the DEP has not included a schedule for its development in the 2002 Integrated List of Waters.  The Town will assess the best method of addressing any TMDLs developed for Sterling’s impaired waterbodies once they are approved.

Stressed Basin Analysis

The Town of Sterling is located in an area identified as “medium” stressed in the December 13, 2001 Massachusetts Water Resources Commission’s (WRC) report entitled Stressed Basins in Massachusetts.  The WRC used streamflow data to locate basins in which the quantity of streamflow has been significantly reduced, the quality of the streamflow is degraded, or the key habitat factors are impaired.  This data was used to classify basins and sub-basins as low stress, medium stress or high stress areas.  The Stressed Basin Analysis was conducted in order to identify areas that may require a more comprehensive and detailed review of environmental impacts or require additional mitigation.  As a component of the SWMP the Town will incorporate the nine standards of the Massachusetts Department of Environmental Protection’s (DEP) Stormwater Policy into the Town’s Protective Bylaws and Subdivision Rules and Regulations.  Standard three of the DEP’s policy indicates that,

“Loss of annual recharge to groundwater should be minimized through the use of infiltration measures to the maximum extent practicable.  The annual recharge from the post-development site should approximate the annual recharge from the pre-development site or existing site conditions, based on soil type.”

Groundwater recharge is often overlooked as a method of mitigating stormwater discharges from developments.  Inclusion of the nine standards in the Town’s regulatory requirements will call for project proponents to thoroughly explore options for groundwater recharge and include them in their stormwater management plan.

Once again we stress that this is only a portion of the Town's Plan.  If you would like to review a copy of the Plan please contact us. Below are some links for further information on this subject.

Stormwater Policies & Guidance

Erosion and Sedimentation Control Guidelines: a guide for planners, designers, and municipal officials
Guidelines with images: Section 1: PDF  1.55 MB | Section 2: PDF 2 MB | Section 3: PDF 1 MB   
Complete Guidelines, without images: PDF 2.24 MB

Historic Properties Eligibility    Web page
NPDES definitions   Web page
Stormwater Best Management Practice Demonstration Tier II Protocol for Interstate Reciprocity
MS Word  355 KB | PDF 156 KB


Stormwater Management Policy      MS Word 69 KB | PDF 47 KB
Stormwater Policy Handbook      Volume I: PDF 200 KB | Volume II: PDF 800 KB