Horn Pond
Middlesex County, Massachusetts103 acresView mapDirections
MassDEP publishes the water-quality measurements for Horn Pond. Here is what has been measured.
- Eutrophic
- Impaired · Algal growth
- 39 ft max depth
- Public access
- Limited data
Horn Pond in Middlesex County, Massachusetts has water-quality measurements published by MassDEP, shown here as reported. Chlorophyll-a (algae): 13.4 µg/L. Surface area: 103 acres.
Horn Pond is a 103-acre productive, nutrient-rich eutrophic lake in Middlesex County, Massachusetts with an estimated average depth of about 39 feet. Limited fish-species data available. Public access is available with 1 public boat landing. Compared to the 10 other monitored lakes in Middlesex County, Horn Pond ranks #8 for water quality.
Source: EPA Water Quality Portal sampling records, MassDEP, last sampled 2019-10-29. Methodology: how these readings are compared.
What Horn Pond is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
Swimming conditions
Readings onlyRecreation use not supported
Based on clarity and algae readings from past sampling — there is no live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Nutrient and algae readings are not a swimming clearance. Horn Pond is listed impaired under Clean Water Act §303(d) (IR 5) for algal growth, habitat alterations, nutrients (phosphorus, nitrogen), oxygen depletion (low DO), pesticides. Check local advisories before you swim.
Whether Horn Pond is safe to swim in today is a call for the Massachusetts Department of Environmental Protection and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Horn Pond
These are the measurements MassDEP publishes for Horn Pond, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
No clarity data. Chlorophyll-a 13.4 µg/L. TSI 56.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | No reading How deep a black-and-white disk stays visible from the surface. Higher is clearer. | |
| Total phosphorus | No reading The nutrient that most limits algae growth in freshwater. More phosphorus, more algae potential. | |
| Chlorophyll-a (algae) | 13.4µg/L | Poor GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 56 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Horn Pond
Answers come straight from the public measurements and survey records on this page.
Lake Details
Max depth
~39 ft est.
Surface area
103 acres
Public access
Yes
Listed by MassDEP
Depth marked “est.” is a modeled maximum from GLOBathy (Khazaei et al. 2022, CC0), not a measured survey. Massachusetts has not published bathymetry for Horn Pond.
Lake Size & Watershed
Watershed (drainage) area
9 sq mi
HydroLAKES / HydroSHEDS
Shoreline
1.7 mi
HydroLAKES / HydroSHEDS
Elevation
46 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS). Mean depth here is modelled, not surveyed — HydroLAKES v1.0 estimates lake depth from surrounding terrain rather than from soundings. Treat it as an approximation, and prefer a state bathymetric survey where one exists.
Recreation & Access
- Horn PondPublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Horn Pond
Compare lakeside cabins, hotels, and vacation rentals near Horn Pond in Middlesex County, Massachusetts — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water. The water-quality readings cover nutrients and algae, not lodging. Cabins and rentals around Horn Pond are listed below.
Top-rated places to stay near Horn Pond
Prices for Oct 30–Nov 1, 4 adults. Change dates on the map below.
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Planning a whole trip? See where to stay at Massachusetts’s top lakes →
Follow Horn Pond’s readings
Email me when new measurements post for this lake. Updates stay free.
Or email
Fishing Horn Pond
Reservoir Info (USACE NID)
Horn Pond is a man-made reservoir impounded by the Horn Pond Dam (completed 1989), built primarily for water supply on the Horn Pond Brook, tributary to Aberjona River; earth-type dam, 15 ft tall and 330 ft long.
- Surface area
- 103 ac
- Normal storage
- 840 ac-ft
- Max storage
- 1,508 ac-ft
- Drainage area
- 9.36 sq mi
- Hazard class
- Significant
- Owner
- City of Woburn
All listed purposes: Water Supply;Recreation.
Source: USACE National Inventory of Dams, NID ID MA01124 · Operator website
EPA Impairment Status
Horn Pond is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 5).
Causes of impairment
Designated uses not supporting: Aquatic life, Fish consumption, Recreation, Other.
Source: EPA ATTAINS assessment unit MA71019 · Official waterbody report
Nearby Lakes in Middlesex County
Frequently asked questions about Horn Pond
Where is Horn Pond?
- Horn Pond is a lake in Middlesex County, Massachusetts. Its water-quality measurements are published by MassDEP and shown on this page as reported.
What is the water quality of Horn Pond?
- Horn Pond in Middlesex County, Massachusetts has water-quality measurements published by MassDEP, shown here as reported. Chlorophyll-a (algae): 13.4 µg/L. Surface area: 103 acres.
Is Horn Pond safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Horn Pond is listed impaired under Clean Water Act §303(d) (IR 5) for algal growth, habitat alterations, nutrients (phosphorus, nitrogen), oxygen depletion (low DO), pesticides. Check local advisories before you swim.
How deep is Horn Pond?
- No published bathymetric survey covers Horn Pond, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 39 feet, but that is a modelled estimate derived from surrounding terrain rather than a measurement on the water, so treat it as approximate. The lake covers 103 acres.
Are there boat ramps on Horn Pond?
- Horn Pond has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Horn Pond. Public access is listed as yes.
Can I fish at Horn Pond?
- Horn Pond has 1 documented boat landing in the USGS National Boat Ramps inventory. Seasons, size and bag limits, and whether you need a license are set by Massachusetts's fish and wildlife agency, so check its current regulations before you go.
Explore Horn Pond across LakeQuality
More lakes in Massachusetts
Other Lakes in Massachusetts
Eutrophic Lakes in Massachusetts
Where this data comes from
5 measurements from 1 monitoring station, 2019. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Massachusetts Department of Environmental Protection (MassDEP)
MASSDEP5 samples · 2019
Analytical methods
- 445.0 ~ EPA; Chlorophyll and Pheophytin in Algae by Fluorescence
Monitoring station identifiers (1)
EPA condition classes from the National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See where the data comes from and data sources.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database
Lake size & watershed from HydroLAKES (HydroSHEDS)
Named boat-access points from the USGS National Boat Ramps inventory