Which Green River
Massachusetts has three Green Rivers that trout anglers talk about, and this page is about the one that ends in Great Barrington. It rises in Canaan, New York, north of Fog Hill Road, runs about 18 miles through Austerlitz and Hillsdale, crosses into Alford, passes through Egremont and joins the Housatonic in Great Barrington; the Housatonic Valley Association's 2017 assessment counts 8.2 of those miles in New York and 10.1 in Massachusetts. The other two, the Green River at Williamstown that runs along Route 7 and Route 43 below Mount Greylock, and the Green River at Colrain and Greenfield with its Wildlife Management Area, are different rivers with their own gauges. MassWildlife lists this one, the Great Barrington Green, as a major river for regulation purposes, and MassDEP classifies its Massachusetts miles as a Class B Coldwater Fish Resource, a designation MassWildlife defines as water used by reproducing coldwater fish. HVA calls it one of the best trout streams in the state.
Bridge to bridge through Egremont and Great Barrington
There is no official public access anywhere on the Massachusetts river, so the fishing is done from road bridges, and the HVA survey walked every section and named them. Coming out of Alford the river runs past the Alford Wildlife Sanctuary and the Egremont Land Trust's North Egremont conservation easement, with bridges at Route 71, Rowe Road and Boice Road; from Boice Road it meanders along Egremont Plain Road to Pumpkin Hollow Road, widening to 30 to 50 feet over clear water and gravel. The section from Pumpkin Hollow Road to Seekonk Cross Road runs past fields and the airport, and the surveyors saw a trout at the Seekonk Cross Road bridge. Below Seekonk Cross Road a big gravel bar and an unofficial swimming hole draw people, and the land is posted. Seekonk Cross Road to Hurlburt Road is a mile and a half of riffles and pools from under a foot to more than four feet deep, with gravel bars and downed trees, mostly under a good forest buffer. Hurlburt Road to the Route 23 and 41 bridge at Maple Avenue is the piece HVA calls beautiful and relatively wild: a flat, gravel-and-cobble mile and a half with pools three to six feet deep, a pump station and a low man-made dam a third of the way down that locals use as a swimming hole, then a sandy bottom toward the bridge. Below Route 23 the river runs through the Wyantenuck Golf Course under two footbridges and past a farm field, where the surveyors again saw trout, before it reaches the Housatonic. Every access is a bridge right-of-way and every bank beyond it is private; the 2017 report notes homeowners complaining about trash at the swimming holes, and that is the fastest way to lose the bridges too.
The gauge under the Hurlburt Road bridge
USGS 01198000, Green River near Great Barrington, is physically under the Hurlburt Road bridge; HVA's survey logged it there as the start of its Section L. It drains 51 square miles. No shop publishes a wading number for a stream this small, so the 25 to 120 cfs band on this page is the gauge's own record and should be read that way: monthly medians since 1951 are about 189 cfs in April, 96 in May, 39 in June, 18 in July, 13 in August and September, 25 in October, 58 in November and 110 in December. At the April median the riffles are pushy and the pools are blown; May is the month; by July a reading in the teens is a normal summer and the fish are in the deep pools and under the wood. The late-September reading this year was 16 cfs. When the number is under 20, the stream is small enough that you can put every fish in a pool down with one bad step.
Spring stocking, and what CFR does and does not tell you
MassWildlife's stocked waters list has the Green River in Alford, Egremont and Great Barrington, all spring-only stockings, which means hatchery browns, rainbows and brookies go in around April and are not replenished in fall. What holds the stream up after June is the reproducing coldwater fish that the CFR designation refers to; MassWildlife's public materials do not say which species reproduce here, and the HVA surveyors recorded trout at Seekonk Cross Road and in the golf course reach without identifying them. So treat the wild browns local anglers talk about as likely but undocumented, and the brook trout in the New York headwaters as the surest wild fish in the system. HVA also flagged possible didymo on the rocks below Route 23 and in the upper river, so clean and dry your boots between streams.
Hatches, by regional chart only
Nobody publishes a hatch chart for a stream this small. The rows below are the FlyFishFinder Massachusetts chart for Berkshire freestones and Berkshire Style's regional notes, which put Hendricksons in early May, March Browns, Brown Drakes and Sulphurs in mid to late May and June, caddis through summer, Isonychia from August and olives in spring and fall. On water this size the useful hatch is whatever is on the bushes: a size 16 caddis, an ant and a small Adams cover most evenings.
Three trout a day, and the posted banks
Because MassWildlife lists the Green River at Great Barrington as a major river, the trout limit is three per day, year-round, with no minimum length, rather than the eight-fish April 1 to September 10 limit on other rivers and brooks. There is no catch-and-release area, no fly-only water and no bait restriction on the Green; the season is January 1 to December 31. The DPH Housatonic advisory covers the Housatonic and the tributaries feeding it from Center Pond Dam in Dalton to the Connecticut line, and the Green enters that reach at Great Barrington, so fish from its lowest mile are inside the do-not-eat zone. Above that the stream is not under a specific advisory, but Massachusetts' statewide advice for recreationally caught fish still applies. Respect the No Trespassing signs at the Seekonk Cross Road bar; the bridges are all there is.