HYDROLOGY & WATER QUALITY CONCERNS

D.W. Field Park sits in the headwaters of the Taunton River Watershed, which in total spans 562 square miles, most of which occurs downstream from the park.

This means that the waters in the park sit at an influential part of the watershed. Improving ecological functioning and stormwater management within the park may have positive implications downstream.

SEVEN HUMAN-MADE WATER BODIES ARE FOCAL FEATURES OF THE PARK

Brockton Reservoir

The reservoir used to supply 5% of Brockton’s drinking water. It has been out of commission since 2020, however, when artificial chemicals per- and poly-fluoroalkyl contaminants were detected (OSRP).

Waldo Lake

At 80 acres, Waldo lake is the largest water body in the park. It is bisected by a causeway which is a major spot for fishing. The Parks and Recreation Department stocks Waldo Lake and Upper Porter Pond with species including trout, perch, pickerel, Large Mouth Bass, and Blue Gills.

Upper Porter Pond

Runoff

Water flowing off roads impacts water quality. It carries contaminants and sediment into lakes and rivers, and warms them. The roads in D.W. Field Park are close to the water, in many places only around 20 feet away. There are many places along the road where paved swales direct water and sediments directly into Waldo Lake and Upper Porter Pond. This arrangement is likely having a negative impact on the quality of these water bodies, though water quality testing is needed to evaluate current conditions.

Fanwort

All of the water bodies in the park are listed as impaired by the state. The cause of the impairment is an invasive aquatic plant called Fanwort.

Brockton

The water in the pond is used to irrigate the D.W. Field Golf Course next door. No algal blooms have been noted in Upper Porter Pond, though the client core team reports that high levels of salt have been detected on the putting greens next door despite the Park Department’s policy of not using salt or sand to maintain roads within the park during the winter.

Lower Porter Pond

Lower Porter Pond is 7 acres, and sits in the southern section of the park, which will be addressed in phase three of the Initiative.

Thirty-Acre Pond

Named after its size, Thirty Acre pond is the largest water body in the bottom third of the park.

Ellis Brett Pond

Water Fowl

Fanwort is an aquatic perennial plant that outcompetes native vegetation, diminishing food sources for fish and wildlife. It forms dense mats of vegetation which block sunlight and deplete oxygen levels in the water, creating anoxic conditions that can cause fish kills and make unpleasant recreation experiences. Fanwort is challenging to manage because it can regenerate easily from small remnants left behind in removal processes.

D.W. Field park is home to large populations of ducks, geese, and swans. Concentrated numbers of these birds can harm vegetation with intense grazing, erode shorelines with frequent use, and make waters clouded and muddy such that other species struggle to survive.

Beaver Brook & Lovett Brook

These two tributaries cross under Route 24 before flowing into the park, causing concerns about salt and runoff from the highway impacting water quality in the park.

Ellis Brett Pond was 6 acres, and was formerly the only natural swimming hole in Brockton-able to accommodate 2,000 people. The pond was filled in in the 1970s, however, due to contaminated runoff from the newly constructed, 600,000 square foot Westgate Mall next door. Since then, the former pond has continued to fill in further from sediment carried there in runoff (OSRP).

Cross Pond

The smallest water body in the park, Cross Pond is the final pond water flows through on its way to Salisbury Brook.

Waterfowl feces can add excess nutrients to water, causing algal blooms and contribute to the spread of water-borne disease (neefusa.org). Satellite images show algae blooms in some waters in the park, including the north half of Waldo Lake.

Dams

A series of dams separates the park’s water bodies. Dams degrade aquatic ecosystems by disrupting the flows of aquatic life, nutrients, and debris. There may be limits to the degree design interventions targeting stormwater can improve ecosystem health for the aquatic plants, fish, and insects in the park.