Always call the town hotline before you go. Bed status changes after rain and for other public-health reasons, and the hotline (not this page) is the authoritative answer.
Most recreational shellfish beds on Long Island Sound are “conditionally approved.” That means they are open only while water quality is good, and they close automatically after heavy rain. This explains why, and how long closures last, using the towns' and states' own wording.
Why rain closes beds
Clams, oysters and mussels filter seawater to feed, so whatever is in the water ends up in the shellfish. Heavy rain washes runoff into harbors and rivers, which can carry bacteria. Branford, for example, lists closures “after heavy rainfall or sewer discharges” (Branford). Rather than test every bed after every storm, regulators set a rainfall trigger. Once it is crossed, the bed closes for a fixed minimum time and reopens only after testing or the end of the closure period.
In Connecticut, only the Department of Agriculture's Bureau of Aquaculture can open or close beds (Fairfield). Harvest is allowed only in Approved and Conditionally Approved areas that are open (CT DoAg).
How much rain? Thresholds differ by town
Many Connecticut towns use about 1½ inches in 24 hours, but not all:
| Town | Rain rule (as published) | Source |
|---|---|---|
| Greenwich | Areas A and B close after >1.5" rain in 24 h for 8 days. | source |
| Darien | Closed after 3" or more of continuous precipitation (town rules). | source |
| Norwalk | Health Dept rain gauge determines status of conditional areas in Norwalk, Darien and Westport under an MOU with the Bureau of Aquaculture. | source |
| Westport | Rain-gauge MOU with Norwalk Health Dept. | source |
| Fairfield | >1.5" in 24 h; rainfall closures typically last at least 7 days. Only the Bureau of Aquaculture can open/close beds. | source |
| Milford | Approved & Conditionally Approved-Open areas only. | source |
| Branford | Closures after heavy rainfall or sewer discharges. Open/closed sign at Limewood Beach. | source |
| Guilford | See state closures; town regs dated 2016. | source |
| Madison | Area C has a 3" rain trigger (town page). | source |
| Waterford & East Lyme (Niantic River) | 1½" in 24 h closes a conditional area for at least 7 days; water samples after 5 days. Red/white signal disks at Rope Ferry Rd launch, Hole in the Wall Beach, Crescent Beach. | source |
| Groton | >1.5" rain closes conditional areas. | source |
How long closures last
- Fairfield: rainfall closures typically last at least 7 days.
- Greenwich: Areas A and B stay closed for 8 days.
- Niantic River: at least 7 days, with water samples taken after 5 days.
- New York: NYSDEC: emergency closures follow rainfall over 3" in 24–36 hours. In summer, when water is warmer, some areas may be closed after LESS than 3". Closures may be extended beyond 7 days if water quality has not improved by day 6. North Shore embayments close at least 3 days and may reopen on day 4 after testing (Stony Brook and Mount Sinai harbors may take longer). Recorded closure line 631-444-0480, updated after 4 PM from day 3–4. (NYSDEC rainfall criteria).
New York's North Shore
On Long Island, NYSDEC issues temporary closures (rain, biotoxins and others) and posts them online (NYSDEC temporary closures). The recorded closure line is 631-444-0480. NY town pages: Oyster Bay, Huntington, Smithtown, Brookhaven (North Shore), Riverhead, Southold.
Rain is not the only reason
Beds can also close for red tide or other biotoxins, Vibrio risk, sewage spills, or administrative reasons. A dry week does not guarantee a bed is open.
What this means for you
- After a big storm, assume conditional beds are closed for about a week.
- Rain totals vary across a town, and the official gauge is what counts, not your backyard.
- Always call the hotline the day you go. Every town page here lists it.
Latest posted status
Every Thursday: which beds are posted open, closures after rain, and season changes. Free, unsubscribe anytime.