Wastewater Discharges

An Environmental Permitting Fact Sheet


Program Overview

This permit program, administered by the Bureau of Materials Management and Compliance Assurance, Water Permitting and Enforcement Division, regulates discharges to waters of the state, including all surface waters, ground waters and Publicly Owned Treatment Works (POTW) (i.e., sewage treatment plants).

DEEP uses both individual and general permits to regulate discharge activities. Individual permits are issued directly to an applicant, whereas general permits are permits issued to authorize similar minor activities by one or more applicants. Authorization of an activity under a general permit is governed by that general permit. Since the general permit process may be quicker and less costly, be sure to check the List of General Permits fact sheet (DEP-FS-004) in order to determine whether any of your discharges may be eligible for authorization under a general permit before applying for an individual permit. Other short processes such as Emergency and Temporary Authorizations may apply to your proposed activity. Consult the Short Permit Processes fact sheet (DEP-FS-003) or call our Permitting staff at 860-424-3018 for further information.

DEEP issues discharge permits in three major categories. While the process for each is similar, specific application requirements may vary.

  • The Surface Water Discharge Permit Program, also known as the National Pollutant Discharge Elimination System (NPDES) under federal law, regulates discharges into surface waters (either directly or through municipal storm sewer drainage systems, or through other drainage systems such as wetlands or swales).

  • The Ground Water Discharge Permit Program regulates discharges to ground water from any source, including but not limited to large septic systems, agricultural waste management systems, and all waste landfills.

  • The Pre-treatment Permit Program regulates discharges to a sewage treatment plant through municipal sanitary sewer drainage systems, or through combined storm and sanitary sewer systems. All wastewaters (excluding domestic sewage) that are hauled directly to a POTW will require either a pre-treatment permit or will be regulated under the sewage treatment plant's permit. Domestic sewage hauled directly to a POTW is regulated by the CT Department of Public Health.

In making a decision on a permit application, DEEP must determine that the proposed discharges will not cause pollution to the waters of the state. In doing this, staff review the potential for: 1) any adverse effects on existing and designated uses of the waters of the state as defined in Connecticut's Water Quality Standards and Criteria; 2) any interference with or adverse effects upon the operation of a POTW; and 3) any systems and methodologies proposed to counteract such adverse effects and to minimize the discharge of pollutants.

Authorizing Statutes

Sections 22a-416 through 22a-438 of the Connecticut General Statutes (CGS)


Sections 22a-430-1 through 22a-430-7 of the Regulations of Connecticut State Agencies (RCSA)


Who Must Apply

Any person or municipality that discharges water, substances, or materials into the waters of the state is required to obtain a permit prior to commencing the discharge. Waters of the state include all surface and ground waters, sanitary and storm sewers. Subsurface discharges of domestic sewage which are not community sewer systems and which have a volume of less than 5,000 gallons per day (gpd) are regulated solely by local health departments in accordance with the Connecticut Department of Public Health.

Required Application Documents

Permit Application for Wastewater Discharges (DEP-WPED-APP-100), including supporting documents such as a USGS topographic quadrangle map (8 ½" x 11" copy or original), Site Plans, Operation and Maintenance Plans of a Treatment System, Spill Control Plans, Description and Plans of Collection and Treatment Facilities, Discharge Analyses; Applicant Compliance Information (DEP-APP-002);  and all other attachments required for your specific application.


Fees are based on wastewater categories and the volume of wastewater discharged. See sections 22a-430-6 and 22a-430-7 RCSA for the schedule of wastewater categories and the associated fees based on the volume of wastewater discharged.

An initial application fee of $1300.00 is required with each application for an individual permit. The balance of the fee is calculated and billed upon completion of the preliminary review of the application.

Review and Processing

Upon receipt of the application package, the initial application fee and, if applicable, the certified copy of the Notice of Application, a preliminary review of the application is conducted for sufficiency and general consistency with applicable standards and criteria. The permit fee for the proposed activity is calculated and any balance due is billed. A detailed technical review is conducted to determine the extent of any adverse impacts on the waters of the state, including any adverse impacts upon the operation of a POTW. This review will include consideration of any treatment systems or other control technology proposed to counteract or mitigate any adverse impacts. Upon completion of this technical review, a tentative determination to grant or deny the permit application will be made by the Commissioner. Where applicable, a Notice of Tentative Determination will be published in a newspaper having general circulation in the affected area and public comments will be solicited on the tentative determination. In some cases, a public hearing may be held. After completion of the technical review and consideration of any public comments and subsequent to the close of any hearing, DEEP will issue a final decision on the permit application. Should the applicant receive a final decision from DEEP to grant the permit, DEEP will require final construction plans and specifications for any collection and/or treatment system to be submitted for approval prior to initiating construction and/or any discharges.

Unique Processing Features

For discharges to surface water, an applicant will be required to conduct a Discharge Toxicity Evaluation (DTE).

For discharges to a POTW, an applicant may be required to receive prior approval from the affected POTW. For large discharges to a POTW an applicant may be required to assess the hydraulic, organic and toxic loading impacts upon the affected POTW.

For discharges of domestic sewage to ground water from land treatment systems, site testing is required prior to submission of an application.

For discharges to ground water, an applicant will be required to evaluate the hydraulic characteristics of the site.

On a case by case basis, the application may be subject to additional review by DEEP's Fisheries Division. If the project has the potential to impact any endangered or threatened species, or species of special concern, or their essential habitats, the application will require additional review by the staff of the Natural Diversity Data Base program. Other specific information may be required for certain discharge categories.

Public Participation

The applicant is responsible for publishing a Notice of Application when the application is submitted to DEEP. Once this notice is published, the applicant must send a copy of the notice to the Chief Elected Official of the municipality in which the regulated activity is proposed, and send a copy of the notice, along with the Certification of Notice Form – Notice of Application (DEP-APP-005A), to DEEP. After the technical review, DEEP will publish Notice of the Tentative Determination to grant or deny the permit (These public notices are not required for certain minor discharges. See exemptions from public notice in RCSA Section 22a-430-2(b)). After this notice, a thirty day comment period is provided where written comments may be submitted and a public hearing may be requested. A hearing will be held upon receipt of a petition signed by at least twenty-five persons and may also be held at DEEP's initiative.

DEEP may require an applicant to post a sign on the site or to provide any other reasonable form of notice necessary to apprise the public and abutting landowners of the proposed activity.

Average Processing Time

For most of this permit program, processing time for a typical application, based upon recent experience is greater than 180 days.  For discharges from domestic sewage treatment works, processing time for a typical application, based upon recent experience is less than 180 days. Past performance is not a guarantee of future processing timeframes.  In order to increase the efficiency of application processing, we recommend that you utilize the Department's Pre-Application Guidance process, assure that your application package is properly completed at the time of submittal, and that you promptly reply to any requests for information.

Permit Duration

Most discharge permits expire after a five year period. For some discharges, DEEP may issue a permit valid for a period of up to ten years. To renew a permit, the permittee must submit a sufficient renewal application at least 180 days prior to the permit expiration date.


A permittee must notify DEEP of a facility or process modification prior to implementing such change. The Facility and Wastewater Treatment Systems Modifications Fact Sheet explains the procedure permittees must follow and provides a link to the form and instructions that must be submitted to DEEP to obtain the approval to commence the modification.


A permit may not be transferred without prior written approval from DEEP. To request a permit transfer, a License Transfer Form (DEP-APP-006) must be submitted, with all required supporting documents, within thirty days of the actual transfer.

Contact Information

Water Permitting and Enforcement Division
Bureau of Materials Management and Compliance Assurance
Department of Energy and Environmental Protection
79 Elm Street
Hartford, CT  06106-5127


This overview is designed to answer general questions and provide basic information. You should refer to the appropriate statutes and regulations for the specific regulatory language of the different permit programs. This document should not be relied upon to determine whether or not an environmental permit is required. It is your responsibility to obtain and comply with all required permits.


Fact Sheet DEEP-WPED-FS-100

Content Last Updated June, 2013


Users Guide to Environmental Permits