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    State of Connecticut

    Connecticut stormwater laws & regulations

    The State of Connecticut operates under the National Pollutant Discharge Elimination System (NPDES) program under the authorization of the U.S. Environmental Protection Agency (EPA) through state regulation Regulations of Connecticut State Agencies R.C.S.A. §§ 22a-430-1— 22a-430-8. The Department of Energy and Environmental Protection (DEEP) manages the permitting and compliance of stormwater discharge.

    Stormwater Associated with Commercial Activities (DEEP-WPED-GP-004): This general permit applies to all discharges from any conveyance which is used for collecting and conveying stormwater and which is directly related to retail, commercial, and/or office services whose facilities occupy five acres or more of contiguous impervious surface. Registration is required to be submitted in order for the discharges to be authorized by this general permit.  Registrations are non-transferrable.

    EXCERPT-General Permit for the Discharge of Stormwater Associated with Commercial Activity


    "Commercial activity" means any activity or facility under Standard Industrial Classifications (SIC) (as defined in “Standard Industrial Classification Manual, Executive Office of the President, Office of Management and Budget 1987”) 50-59 and 70-79, with five (5) acres or more of contiguous impervious surface. Impervious surface means roof area, paved walk, paved parking area, paved driveway, paved roadway and any other paved surface. An activity or facility with an SIC code already covered by the General Permit for the Discharge of Stormwater Associated with Industrial Activity is not included in this definition. See Appendix A for SIC code descriptions.


    B. STORMWATER MANAGEMENT PLAN. The permittee shall prepare, implement and maintain a Stormwater Management Plan (the “Plan”) which shall consist of all records, schedules, narrative, instructions or other materials kept on file at the registrant’s facility in accordance with the Stormwater Management Measures and other provisions of Part V of this general permit.

    2. Stormwater Management Measures

    The Stormwater Management Plan shall be maintained on a form prescribed and provided by the Commissioner and shall, at a minimum, contain the following:

    a. Pollution Prevention Team

    The permittee shall designate a Pollution Prevention Team consisting of personnel, at least one of who must be working at the site, to carry out the provisions of these Stormwater Management Measures.

    b. Sweeping

    All parking areas, sidewalks, driveways and other impervious surfaces (except roofs) shall be swept clean of sand, litter and any other possible pollutants at least twice a year, once between November 15 and December 15 (after leaf fall) and once during the month of April (after snow melt) and at other times as may be necessary.

    c. Outside Storage

    Any raw materials, intermediate products, by-products, final products, waste materials, accessories or equipment stored outside shall be covered or moved inside, if possible, or maintained in such as manner as to avoid, if at all possible, the risk of any of these materials or their residue passing to a stormwater discharge.

    d. Washing

    No water resulting from washing of any raw materials, intermediate products, by-products, final products, waste materials, accessories, equipment, storage areas, outside sales/garden areas, loading docks, parking areas or vehicles shall be discharged to a stormwater collection system or waters of the state (including, but not limited to, surface waters or wetlands) except in accordance with a permit issued by the DEEP pursuant to Section 22a-430 or 22a-430b of the Connecticut General Statutes.

    e. Spill Control

    The permittee shall prepare and implement a Spill Control and Response Plan (“Spill Plan”) for any raw materials, intermediate products, by-products, final products, waste materials, accessories or equipment present at the facility which could possibly discharge to the stormwater collection system or waters of the state. The Spill Plan shall include measures to avoid spills in areas exposed to rainfall or from reaching areas exposed to rainfall. The Spill Plan shall also include response measures to best prevent a spill from being exposed to stormwater or entering a stormwater collection system or waters of the state once it has occurred.

    The Spill Plan shall identify areas where potential spills can occur and the location of associated collection and discharge points. The Spill Plan shall include procedures for cleaning up spills including, without limitation, procedures for insuring that appropriate personnel are trained or otherwise notified of measures to take in the event of a spill. The necessary equipment to implement a cleanup shall be listed in the Spill Plan and locations designated such that this equipment shall be available to personnel in all areas where spills may occur. The Spill Plan shall provide that all areas in which a spill could potentially discharge to stormwater and where liquid chemicals are stored are provided with impermeable containment which will hold at least the volume of the largest chemical container, or 10% of the total volume of all containers in the area, whichever is larger, without overflow from the containment area. For commercial activities initiated after the date of this general permit, the Spill Plan shall provide that all chemicals in containers of 100 gallons or less shall be stored under a roof that minimizes stormwater entry to the containment area.

    The Spill Plan shall also provide that all dumpsters used to store waste or recyclable materials are supplied with attached covers and have drain plugs intact, or are in roofed areas that will keep rain out of the dumpster and will not allow dumpster leakage to enter any stormwater drainage system.

    f. Maintenance and Inspection

    The permittee shall prepare and implement a facility maintenance plan. The facility maintenance plan shall include good housekeeping measures to ensure that all areas exposed to stormwater are kept in such a condition as to minimize the possibility of discharging pollutants into a stormwater collection system or waters of the state. The plan shall include provisions for a monthly inspection by a member of the Pollution Prevention Team of all areas covered by the plan, a weekly inspection of the site for surface debris and the monthly inspection of all stormwater structures and outfalls on the site for floating or surface debris and sediment. Structures and outfalls shall be cleaned of sediment and debris at least once a year during the month of April and at other times as necessary to prevent the discharge of pollutants from structures or outfalls.

    g. Employee Training

    The permittee shall ensure that all employees whose activities may affect stormwater quality receive training upon employment and at least once a year thereafter to make them familiar with these stormwater management measures. Training shall be conducted by a member of the Pollution Prevention Team.

    h. Comprehensive Annual Stormwater Evaluation and Inspection

    Once a year, a member of the Pollution Prevention Team shall conduct a Comprehensive Annual Stormwater Evaluation and Inspection. All aspects of the stormwater collection and/or treatment system shall be inspected for consistency with the Stormwater Management Plan. A report of the results of this inspection shall be prepared and a copy maintained on site. This report shall also be reviewed and signed by the permittee as specified in Part IV.C.2.c. above. Based on this report, the permittee shall revise the Plan as necessary to maintain consistency with this general permit.

    i. Record Keeping

    The permittee shall keep at the site a record of all weekly and monthly inspections, the facility spill control and response plan, sweeping schedule, stormwater structure cleaning schedule, employee training schedule, annual stormwater evaluation and inspection reports and a list of designated Pollution Prevention Team members. This record shall be made available to the Commissioner for inspection immediately upon request.

    j. Future Construction

    The permittee shall ensure that oil and sediment control structures or devices are used within the drainage system for all construction which i) may impact the drainage system and ii) occurs on site on or after the effective date of this general permit. Note that any construction activity that disturbs greater than 5 acres must be registered and conducted in accordance with the General Permit for the Discharge of Stormwater and Dewatering Wastewaters from Construction Activities, as amended. In addition, the permittee shall avoid, wherever possible, the use of copper or galvanized roofing or building materials for any new construction where these materials will be exposed to stormwater.

    3. Keeping Plan Current The permittee shall update the Plan annually and shall amend the Plan whenever; (1) there is a change at the site which may affect the potential of stormwater discharges from the site to cause pollution of the waters of the state; (2) there is a change in the Pollution Prevention Team; (3) the actions required by the Stormwater Management Measures fail to ensure or adequately protect against pollution of the waters of the state; or (4) the Commissioner requests modification of the Plan. The permittee shall amend the Plan as necessary to address any sources or potential sources of pollution identified as a result of a Comprehensive Annual Stormwater Evaluation and Inspection conducted pursuant to Part V.B.2.h. of this general permit. The amended Plan and all actions required by the Plan shall be completed within 60 days of the date the permittee becomes aware or should have become aware that any condition identified in this paragraph has occurred.


    1. The permittee shall keep a copy of the Stormwater Management Plan onsite at all times. The permittee shall make a copy of the Plan available to the Commissioner immediately upon request, and, in the case of a stormwater discharge associated with commercial activity that discharges through a municipal separate storm sewer system, to the operator of the municipal system upon request. In the case of a stormwater discharge associated with commercial activity that discharges to a water supply watershed, copies of the Plan shall be made available upon request to the public water supply company.

    2. The Commissioner may notify the permittee at any time that the Plan does not meet one or more of the requirements of this Part. Unless otherwise notified by the Commissioner in writing, within 30 days of the date of such notification from the Commissioner, the permittee shall revise the Plan, perform all actions required by the revised Plan, and shall submit to the Commissioner, in writing, certification that the requested changes have been made and implemented and such other information as the Commissioner may require.

    Purpose: These guidelines have been developed to clarify DEEP recommendations to state and municipal officials, and others regarding the removal and disposal of snow accumulations from roadways and parking lots. For purposes of this guidance snow accumulations refers to snow banks and snow piles that are removed by front-end loader or by loading on trucks for disposal. This guidance does not apply to normal snow plowing operations that must, inevitably, discharge some snow into wetlands and watercourses.

    Implementation: While following these guidelines does not constitute a permit or authorization, the Department recognizes there is a considerable need for flexibility in implementation of this policy, particularly in emergency situations. There is no intent to interfere with snow plowing operations. Where trucking and snow dumping operations are undertaken the Department recommends these guidelines be followed.

    Recommended Management Practice: Snow accumulations removed from roadways, bridges, and parking lots should be placed in upland areas only, where sand and other debris will remain after snowmelt for later removal. Care must be exercised not to deposit snow in the following areas:

    • freshwater or tidal wetlands or in areas immediately adjacent to such areas where sand and debris may be flushed during rainstorms;
    • on top of storm drain catch basins;
    • in storm drainage swales;
    • on stream or river banks which slope toward the water, where sand and debris can get into the watercourse; and
    • in areas immediately adjacent (within at least 100 feet) of private or public drinking water well supplies (due to the possible presence of road salt).

    Notification:  Notification can be made by addressing an email to Dahlia Gordon at: [email protected].  The notification must include the following: (1) the name of the governmental entity making the notification; (2) contact information for the governmental entity including name, email address and phone number; (3) the street address where the snow disposal activity will occur; (4) the name of the waterbody where the snow will be disposed; (5) the estimated quantity of snow to be disposed; (6) the dates during which the disposal activity will occur; and (7) a statement that the governmental entity has exhausted all disposal alternatives and snow management methods and will make best efforts to adhere to these snow disposal guidelines.

    Information: For further information please call the Water Permitting and Enforcement Division Engineer of the Day at 860-424-3025.

    Supplemental Documents:

    DEEP Stormwater Management Website

    Commercial Activity General Permit Registration 

    Regulations of Connecticut State Agencies