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Aquatic Pesticide Application

An Environmental Permitting Fact Sheet


Program Overview

The Aquatic Permit program, administered by the Connecticut Department of Energy and Environmental Protection's (DEEP), Bureau of Materials Management and Compliance Assurance, regulates the use of chemicals proposed for introduction into the waters of the state, whether public or private, for control of aquatic organisms. These organisms are usually aquatic weeds or algae, but could include mosquitoes or unwanted fish. Applications are evaluated for the potential of causing unreasonable adverse effects to human health or the environment. Only chemicals registered for aquatic sites may be used.

Authorizing Statutes

Section 22a-66z, 22a-66a(h) of the Connecticut General Statutes (CGS)


Sections 22a-66z-1, 22a-66a-1(e) of the Regulations of Connecticut State Agencies (RCSA)

Who Must Apply

Any person who wishes to control organisms in the waters of the state with chemicals.

Required Documents

Permit Application for Use of Pesticides in State Waters (DEEP-PEST-APP-200) including supporting documentation such as a USGS topographic quadrangle map (8 ½" x 11" copy or original); Applicant Compliance Information (DEEP-APP-002) and if applicable, the Coastal Consistency Review Form (DEEP-APP-004) and the Request for NDDB State Listed Species Review Form (DEEP-APP-007)


The yearly application fee associated with this permit is $200.00.

Review and Processing

Permit applications are reviewed by the Pesticide Program. When the waterbody to be treated is in a public water supply watershed, or a tributary to such a water supply, additional criteria required by the CT Department of Public Health are applied to the review. Only chemicals which have been registered for use in aquatic sites are permitted.

Unique Processing Features

If the proposed treatment 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 in the DEEP Natural Diversity Data Base (NDDB) Program. Please note NDDB review generally takes 4 to 6 weeks and may require additional documentation from the applicant. DEEP requires that applicants complete this process before submitting their permit application. If applicable, a copy of the completed Request for NDDB State Listed Species Review Form and the CT NDDB response must be submitted with a completed application.

If the waterbody to be treated is located within the coastal area and the pesticide application is located in an area that is subject to the ebb and flow of the tides, or is inundated by saline or brackish water at least once a month, the application must include a completed Coastal Consistency Review Form so that CT DEEP can determine if the proposed treatment is consistent with the standards and policies of the Connecticut Coastal Management Act.

Public Participation

There are specific requirements in the regulations for the notification of the application of pesticides. In general, in places of public access, a sign must be posted which includes information on waiting periods before water use. In addition, the applicator must publish a newspaper notice of the pending treatment.

Average Processing Time

Preliminary Sufficiency Determination
Secondary Sufficiency Determination
Issuance or Denial

14 days
7 days
21 days

Permit Duration

The permit is valid for the number of chemical applications specified on the permit and usually expires on December 31st of the year in which it was issued.

Contact Information

Pesticide Program
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 (as noted above) 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-PEST-FS-200

Content Last Updated December, 2014


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