Grass River fishing guide
A 74-mile river in St. Lawrence County, New York. The state agency lists 10 species here and last stocked it in May 2025. It has 1 public access point and 1 live sensor on the water.
Today's fishing forecast
LiveLoading today's forecast…
Hour by hour
Bite windows
Next 7 days
Live sensors on this water
- Grass River at Chase Mills NY · flow, water level · USGS 04265432
Grass River flow
Flow gauge: Grass River at Chase Mills NY, USGS 04265432 . The forecast above shows its latest reading and band: Fishable up to this month's typical high (75th percentile), High up to the 90th percentile, Blown out above that.
Typical flow by month
Typical is the middle half of daily mean flows in that month (25th to 75th percentile), from 20–21 years of USGS records.
| Month | Typical flow (cfs) | Median (cfs) | Blown out above (cfs) |
|---|---|---|---|
| January | 445–1,040 | 714 | 1,987 |
| February | 341–833 | 493 | 1,566 |
| March | 686–2,233 | 1,220 | 3,311 |
| April | 1,130–2,888 | 1,815 | 4,093 |
| May | 566–1,540 | 906 | 2,650 |
| June | 363–939 | 574 | 1,621 |
| July | 270–669 | 417 | 1,220 |
| August | 166–575 | 307 | 920 |
| September | 150–392 | 244 | 604 |
| October | 295–859 | 429 | 1,842 |
| November | 558–1,230 | 821 | 2,100 |
| December | 667–1,520 | 980 | 2,422 |
Fish species in Grass River
Species on the official fishing-waters list from New York State Department of Environmental Conservation, then species known only from stocking. Species links open our guide to that fish in New York.
| Species | Status | Last stocked |
|---|---|---|
| Black Crappie | Agency list | — |
| Common Carp | Agency list | — |
| Largemouth Bass | Agency list | — |
| Muskellunge | Agency list | — |
| Northern Pike | Agency list | — |
| Smallmouth Bass | Agency list | — |
| Walleye | Agency list | — |
| Yellow Perch | Agency list | — |
| Brook Trout | Stocked | May 2022 |
| Brown Trout | Stocked | May 2025 |
Stocking history
Last stocked May 2025: brown trout catchable and brown trout yearling. 25 stocking records in the last 10 years, 18,080 fish in all, from New York State Department of Environmental Conservation. Each row below sums the agency's records for one month, species and size.
| Date | Species | Size | Fish stocked |
|---|---|---|---|
| May 2025 | Brown Trout | catchable | 140 |
| May 2025 | Brown Trout | yearling | 1,270 |
| May 2024 | Brown Trout | catchable | 1,360 |
| May 2023 | Brown Trout | catchable | 730 |
| May 2022 | Brook Trout | catchable | 1,280 |
| May 2022 | Brown Trout | catchable | 860 |
| May 2021 | Brown Trout | catchable | 2,170 |
| May 2020 | Brown Trout | yearling | 660 |
| Apr 2020 | Brown Trout | yearling | 2,130 |
| Jun 2019 | Brown Trout | yearling | 2,570 |
| Jun 2018 | Brown Trout | yearling | 2,520 |
| May 2017 | Brown Trout | yearling | 2,390 |
Plus 2 stocking records before October 2016 in the agency data.
Public access and boat launches
1 boat ramp from New York State Department of Environmental Conservation; orange dots on the map above.
- Grass River boat launchRamp
Regulations
No special regulations for Grass River in our data. New York statewide rules apply unless the agency lists a special rule for this water. Seasons, limits and size rules change: check New York fishing regulations before every trip.
Licence: New York fishing licences from New York State Department of Environmental Conservation.
Grass River fishing FAQ
What fish are in Grass River?
New York State Department of Environmental Conservation lists 10 species for Grass River: black crappie, common carp, largemouth bass, muskellunge, northern pike, smallmouth bass, walleye and yellow perch, plus 2 more in the table above.
When was Grass River last stocked?
New York State Department of Environmental Conservation last stocked Grass River in May 2025 with brown trout. Our data has 25 stocking records in the last 10 years.
Where can I launch a boat on Grass River?
The agency lists 1 boat ramp for Grass River, near Morley. Each one is listed in the access section with parking and toilets where the agency records them.
Is there a flow gauge on Grass River?
Yes. USGS gauge 04265432 (Grass River at Chase Mills NY) measures flow on Grass River. Its median daily flow runs from about 244 cfs in September to 1,815 cfs in April. Today's reading is in the forecast at the top of this page; the flow section has the typical range by month.
Sources: New York State DEC, Boat launch sites · New York State DEC, Recommended Fishing Lakes and Ponds (mw8j-wduf); Recommended Fishing Rivers and Streams (tjny-fki3), on data.ny.gov · New York State DEC, Fish stocking lists on data.ny.gov · U.S. Geological Survey, Geographic Names Information System, domestic names · U.S. Geological Survey, National Hydrography Dataset, high resolution, state geodatabases (NHDWaterbody, NHDFlowline); 3DHP when it replaces it · U.S. Geological Survey, Water Data OGC API (monitoring locations, discharge, gage height, water temperature). Checked: Oct 4, 2026. Official links open the agency page. How we use data