Neponset River Watershed Report Cards
EPA and the Neponset River Watershed Association will use the Neponset River Report Card to measure and evaluate progress towards meeting the State of Massachusetts bacterial water quality standards for swimming and boating as well as to assess general health of the watershed.
Grading Criteria
The Neponset River Watershed Association (NepRWA), in coordination with EPA, will use an assessment method that encompasses 26 separate stretches of water bodies in the East Branch, Upper, and Lower Neponset sub-watersheds. These grades provide the public with a more accurate assessment of local water quality conditions and greater transparency for all stakeholders. The report card will be based on E. coli data from thirty-one sampling sites, collected monthly by NepRWA volunteers. This grading system measures the percentage of time water quality samples meet state bacterial swimming and boating standards.
Neponset River Watershed Water Quality Grades and Compliance Rates
| Site | 2023 | 2022 | 2021 | 2020 | ||||
|---|---|---|---|---|---|---|---|---|
| Grade | Total | Grade | Total | Grade | Total | Grade | Total | |
| Beaver Brook | B | 77.8% | B | 78.3% | B+ | 80.2% | A- | 86.3% |
| Beaver Meadow Brook | B- | 72.0% | B- | 73.5% | B- | 74.1% | B- | 71.8% |
| East Branch | A | 94.3% | A- | 89.6% | A- | 86.3% | A- | 86.7% |
| Massapoag Brook | B+ | 81.3% | B+ | 84.8% | A- | 89.6% | A- | 89.7% |
| Pequit Brook | C- | 59.0% | D+ | 54.2% | C- | 59.1% | C- | 58.4% |
| Steep Hill Brook | B+ | 81.1% | B+ | 84.9% | A- | 86.2% | A- | 86.2% |
| Site | 2023 | 2022 | 2021 | 2020 | ||||
|---|---|---|---|---|---|---|---|---|
| Grade | Total | Grade | Total | Grade | Total | Grade | Total | |
| Mother Brook | B+ | 84.8% | A- | 87.4% | B+ | 83.4% | B | 79.8% |
| Lower Neponset River | B | 78.0% | B- | 70.9% | B- | 72.0% | B- | 74.4% |
| Pecunit Brook | C | 63.4% | C- | 59.3% | B | 75.1% | B- | 70.6% |
| Ponkapoag Brook | B | 78.1% | B | 76.5% | B | 75.2% | B | 75.7% |
| Pine Tree Brook | C- | 58.4% | D+ | 52.6% | C- | 55.7% | C | 62.1% |
| Purgatory Brook | B- | 73.4% | C | 60.4% | C | 60.2% | D- | 45.0% |
| Unquity Brook | D+ | 51.3% | D- | 44.7% | F | 33.6% | F | 31.4% |
| Site | 2023 | 2022 | 2021 | 2020 | ||||
|---|---|---|---|---|---|---|---|---|
| Grade | Total | Grade | Total | Grade | Total | Grade | Total | |
| Germany Brook | D+ | 50.9% | D- | 43.8% | D+ | 50.0% | D+ | 50.1% |
| Hawes Brook | C | 64.1% | C | 64.4% | C+ | 67.8% | C+ | 69.3% |
| Meadow Brook | F | 29.8% | F | 28.7% | F | 25.1% | F | 24.1% |
| Mine Brook | B+ | 84.5% | B+ | 80.6% | B+ | 83.4% | B | 76.0% |
| Mill Brook | B | 75.8% | B | 76.4% | B | 77.8% | A- | 89.5% |
| Turner Pond (Walpole) | A+ | 100.0% | A+ | 99% | A+ | 96.7% | A+ | 98.6% |
| Crack Rock Pond | A+ | 95.3% | A+ | 96.6% | A+ | 100.0% | A+ | 97.3% |
| Upper Neponset River | B | 79.0% | B | 77.2% | B | 75.8% | B | 76.8% |
| Ganawatte Farm Pond | A | 90.6% | A | 91.9% | A+ | 97.3% | A+ | 96.8% |
| Spring Brook | A- | 85.9% | B | 79.7% | B | 77.9% | B+ | 81.8% |
| Traphole Brook | D | 49.7% | D | 47.8% | C | 61.2% | C | 63.0% |
| Willet Pond | A+ | 95.8% | A+ | 95.6% | A | 93.0% | A+ | 96.1% |
*Figures represent average percentage of time that state bacterial standards are met.
For more information on the Neponset River Watershed and the grading system, please see NepRWA’s Website.