1.7 Connecticut Use Restrictions, Water Protection & Aquatic Permits
Key Takeaways
Connecticut bans applying neonicotinoids to linden or basswood trees and to plants while they bear blossoms, except in pollinator-proof greenhouses.
Since January 1, 2023, Connecticut prohibits chlorpyrifos on golf courses and for any cosmetic or nonagricultural use.
Hoses drawing from a water supply need a check valve or anti-siphon device, and no spray water may come from streams feeding drinking reservoirs.
Discarding any pesticide into a public sewage disposal system is prohibited under RCSA § 22a-65-1.
Adding any chemical to Connecticut waters to control aquatic organisms requires a DEEP permit costing $200 per year and lasting up to 3 years.
1.7 Connecticut Use Restrictions, Water Protection & Aquatic Permits
Federal registration is only the first gate. Connecticut adds its own registration, a list of banned or limited products, outright bans on certain uses, water-source safeguards, a disposal rule, and a permit system for any chemical added to state waters. These rules apply to every certificate holder, and several of them — the anti-siphon rule, the sewer disposal ban, aquatic permits, and the neonicotinoid limits — are favorite exam items because they differ from federal law.
Registration and Sale
- A pesticide must be registered with EPA and with DEEP to be lawfully applied in Connecticut. Using or selling an unregistered pesticide is a prohibited act (CGS § 22a-61(a)(1)).
- Restricted use pesticides may be sold only to a certified commercial supervisor, a certified private applicator, or a registered seller (CGS § 22a-57(a)).
- Permit use pesticides may be sold only to a person holding the required DEEP permit, or to a registered seller (§ 22a-57(b)).
- Connecticut may classify products as restricted beyond EPA's list. CGS § 22a-50(l) directed DEEP to classify all neonicotinoids labeled for treating plants as restricted use by January 1, 2018.
Banned and Purpose-Limited Products — RCSA § 22a-66-2
Under § 22a-66-2(a), DEEP will not register, and no one may use, products including:
- arsenic products (with narrow exceptions such as MSMA, DSMA, cacodylic acid, and sodium arsenate for lumber treatment);
- BHC, DDD, DDT, Mirex, Strobane, and toxaphene;
- cadmium, lead, selenium, and thallium products, and phosphorus paste;
- mercury products, except inorganic mercury for winter turf diseases on golf courses. Even that use is barred within 250 feet of the high-water line of a potable water supply reservoir, 100 feet of watercourses leading to a reservoir, 200 feet of groundwater wells, on slopes of 15% or more draining to watercourses, and on other sensitive land.
Other products are allowed only for listed purposes (§ 22a-66-2(b)): strychnine only for rat and mouse control; sodium fluoride only as a wood preservative; lindane only for leafminer, bark beetle, powder post beetle, or borer control, or as prescribed for humans by a licensed physician or for animals by a licensed veterinarian; and heptachlor only for subterranean termites by soil injection, trenching, or soil incorporation. Many of these chemicals no longer have federal registrations, but the rule shows Connecticut's approach: the state can be stricter than the label.
Specific uses are also prohibited (§ 22a-66-2(c)):
- Thermally activated pesticides (foggers using heat) indoors, except pyrethrum, pyrethrins, or pyrethroids, or indoor agricultural uses.
- Captan on pets or other animals.
- Chlordane indoors except by Connecticut-licensed applicators, on animals except by veterinarians, or in mist blowers or thermal foggers.
- Tributyltin (TBT) antifouling paint, except products with a release rate of 4.0 micrograms per square centimeter per day or less, applied in a commercial boatyard to vessels longer than 25 meters or to aluminum hulls, or outboard and lower-drive paints in spray cans of 16 ounces or less.
Microencapsulated methyl parathion — RCSA § 22a-66-2b
This rule shows how Connecticut protects bees. Microencapsulated methyl parathion may be used only for San Jose scale in orchards, or for first-generation European corn borer on sweet corn from January 1 through June 30. Before applying, the field or orchard and any drift-exposed borders must be kept as free of flowering ground cover as possible by mowing, herbicide, or other means. DEEP recommends no application when there are more than five flowers per square yard. The reason, explained in DEEP's honey bee manual, is that the microcapsules are about the size of pollen grains, so foraging bees carry them back to the hive.
Statutory Use Bans
| Statute | Rule |
|---|---|
| CGS § 22a-61a | No person may apply, in any manner, any neonicotinoid insecticide to any linden or basswood tree. |
| CGS § 22a-61b | No person may apply a neonicotinoid labeled for treating plants to any plant while it bears blossoms, unless the plant is grown in a greenhouse inaccessible to pollinators and the use follows best practices for pollinator-safe plants. Academic research is exempt. |
| CGS § 22-61k | Defines neonicotinoid: any pesticide acting selectively on nicotinic acetylcholine receptors, including clothianidin, dinotefuran, imidacloprid, and thiamethoxam, plus any other DEEP determines kills 50% or more of bees at 2 micrograms or less per bee. The section also directed best practices for reducing neonicotinoid dust from treated seed. |
| CGS § 22a-61c (effective Jan. 1, 2023) | No person may use or apply chlorpyrifos on any golf course or for any cosmetic or nonagricultural use; civil penalty up to $2,500. |
| CGS § 22a-66n (since Jan. 1, 2019) | No person may install or use a residential automatic pesticide misting system, meaning a device on or around a home's exterior that sprays pesticide at timed intervals. |
| CGS § 22a-54(e)(6) | No aircraft or misting-type application of pesticides or fungicides to shade tobacco within 300 feet of an inhabited home with a certificate of occupancy issued before Jan. 1, 1997, without the owner's written permission (sprays inside the netting excepted). |
Aerial application also needs DEEP aircraft certification and permits (§ 22a-54(e)). Permits for spraying congested areas require the local health director's approval, except for DEEP-declared disease-vector emergencies.
Protecting Water Supplies — RCSA § 22a-66-3
- Anti-siphon protection: every hose used to draw water from a water supply must have a check valve or anti-siphoning device if a reversal of flow could let pesticide into the hose. The discharge side of a pump shall not be connected to any water system.
- Filler hoses used to draw water from watercourses must be covered except when in use.
- No water for pesticide applications may be drawn from any stream or pond leading to a potable water supply reservoir.
- A federally restricted use pesticide may be used only under the supervision of a certified applicator.
The national core manual adds best practices that support these rules. Keep an air gap of at least twice the diameter of the fill pipe between the hose and the tank's liquid surface. Mix and load at least 50 feet from wells, lakes, streams, rivers, and storm drains, preferably at the application site or on a containment pad. Never store or mix pesticides around wells.
Discarding Pesticides — RCSA § 22a-65-1
No person may discard any pesticide or container in a manner that pollutes any waterway or endangers plant and animal life or public health and safety, and discarding any pesticide into a public sewage disposal system is prohibited. The operator manual puts it simply: spilled pesticides and mixtures "should never be washed down storm drains or into the street." Absorb them and dispose of them properly, and report every spill to DEEP's Emergency Response Unit at 860-424-3338, which operates 24 hours a day.
Chemicals in State Waters — CGS § 22a-66z and RCSA § 22a-66z-1
No person may introduce any chemical into the waters of the state to control aquatic vegetation, fish populations, or other aquatic organisms without a DEEP permit.
| Element | Rule |
|---|---|
| Application contents | Applicant; type of area (tidal waters, pond, etc.); whether it is in a public water supply watershed; name and size of the area; owners; organisms to control; fish species present; chemicals and quantities; who will treat; signature |
| Public water supply | No permit is issued without prior Department of Public Health approval if the area is tributary to a reservoir, lake, pond, or stream used for public water supply |
| Fee | $200 per year of permit; nonrefundable; statute sets a floor of $40 |
| Term | Expiration date set by DEEP, not more than 3 calendar years after issuance |
| Reporting | Report pesticide use under each permit by January 31 of the following year |
| Purchase | A permit-use aquatic pesticide may be sold only to a permit holder or to a supervisor certified in the required category. The distributor signs the permit at the sale, after which it is no longer valid for further purchases. |
| Liability | The permittee is responsible for any and all damages from the application |
| Category | Commercial work needs Category 5 (Aquatic); DEEP notes that each application to any water body requires an aquatic permit |
Public notice of lake and pond treatments (newspaper notice, shoreline signs, and abutter notice) comes from § 22a-66a(h), covered in Section 1.5. The permit rule does not apply to normal, emergency, or experimental operations of DEEP, the Department of Public Health, or public water utilities, though those still need DPH approval for public water supplies. Lime used by DEEP to control starfish on shellfish beds is not treated as a pesticide (§ 22a-47a).
Tip
Exam pattern: "Where may you NOT fill a spray tank?" The Connecticut-specific answer is any stream or pond leading to a potable water supply reservoir. The universal answer is any source without a check valve, anti-siphon device, or air gap.
A crew needs water for a 300-gallon tank. Which source is specifically prohibited by RCSA § 22a-66-3?
A nurse tank of clean water hauled from the shop
A stream or pond leading to a potable water supply reservoir
A municipal hydrant used with a check valve
A well on the customer's property used with an air gap
A landscaper wants to apply imidacloprid to a flowering crabapple in full bloom at a client's home. What does Connecticut law say?
It is prohibited, because a neonicotinoid labeled for plants may not be applied to a plant bearing blossoms outside a pollinator-proof greenhouse
It is allowed if the landscaper notifies registered beekeepers 48 hours ahead
It is allowed if the label lists crabapple
It is allowed after sunset when bees are not foraging
A homeowners' association asks a supervisor to treat algae in a private pond. What is required before adding an algaecide to the water?
A DEEP permit under CGS § 22a-66z, with Department of Public Health approval if the area is tributary to a public water supply
A town inland wetlands permit, which replaces the DEEP permit
Only the association's written consent
Nothing, if the pond is privately owned and the product is general use
Sections you finish are checked off in the contents.