Cold Spring Brook: A Drainage Ditch that Wants to be a Stream Again...

Upper Cold Spring Brook within Cold Spring Park in Newton, Massachusetts.

While many urban and suburban public lands are centered around waterways, the primary focus is usually on recreation and riparian health, not aquatic health. We build parking lots, ballfields, playgrounds, dog parks, trails, bridges, boardwalks, park benches, and workout infrastructure. There are bathroom facilities, trash receptacles, maps, and informational signs and kiosks. Caretakers, mostly volunteers, remove nonnative plants, rope off delicate vegetation, and reroute foot traffic away from fragile areas.

Meanwhile, the centerpieces of these public areas, rivers and streams, are often all but ignored. While trails, boardwalks, and bridges are maintained and kept clean for aesthetic and safety reasons, the abutting waterways often contains trash and other debris, some of which has sat unaddressed for years or even decades. And in many cases, these streams can no longer support aquatic lifeforms due to extensive habitat degradation, water drawdowns, and point and nonpoint source pollution…

Trees, branches, planks, and pallets in Cold Spring Brook…

As suburban streams go, Cold Spring Brook in Newton, Massachusetts, has suffered greatly at the hands of man. While it somehow escaped being walled in or run through open top culverts as many suburban streams are, starting roughly 150 years ago, the stream has been moved, straightened, dredged, buried, and impounded. Today, in sections where it is still open to the air, Cold Stream Brook looks more like a drainage ditch than a natural stream…

Today, much of Cold Spring Brook within Cold Spring Park looks more like a drainage ditch than a stream…

The Massachusetts chapter of NFC recently undertook a project to take a look at Cold Spring Brook. Thought to be fishless by those closest to it, members of MA NFC went to the stream to take a look for themselves. What they found was a heavily manipulated stream sans any sinuosity, instream structure, or natural banks, and filled with generations of decaying organic matter. But the water still flowed even though the area was under “severe drought” conditions. Most importantly, they saw fish…

Working with Friends of Cold Spring Park and Newton Conservators, members of MA NFC returned to Cold Spring Brook to try to confirm the presence of fish. With the aid of a seining net, the group was able to capture several golden shiners from an area that had recently been dredged to control stormwater. While the shiners may have been introduced as a result of someone disposing of unused bait, based on their size they appear to be naturally reproducing.

A juvenile golden shiner from Cold Spring Brook.

A few weeks later, several members of the NFC National Board joined the local team onsite for a tour of Cold Spring Brook within Cold Spring Park. What they saw was a small shallow heavily manipulated stream flowing on top of 3-4 feet of decaying organic matter. This greatly impacts what can and cannot live in the stream, including insects, crustaceans, fish, and amphibians, and everything that depends on them.

Generations after being dredged, the Cold Spring Brook streambed is now almost level with the surrounding terrain. As a result of relatively stable flows that limit scouring and a lack of instream structure, there are very few defined channels, and in most places the water is less than 6 inches deep. The streams flows slowly sans any drops or even notable riffles.

Shallow relatively clear water flowing on top of 3-4 feet of decaying organic matter at Cold Spring Brook…

There are however some areas where Cold Spring Brook is beginning to return to a more natural state.  Some sections have developed slight meanders and deeper and more defined channels as a result of natural tree fall, as well as vegetation anchoring on small islands of decaying organic matter.  In some sections one side of the streambed has risen enough to push the water to the opposite bank. 

While these small, vegetated islands are unstable and unable to support any weight, they show a stream that is trying to heal itself after generations of abuse and neglect. With a little help in the form of manual channel dredging, it may be possible to lower the water table in these areas enough to dry the islands to a point where they can support some level of brush growth which would help stabilize them.  

A section of Cold Sprong Brook where grass has taken root on top of islands of accumulated decaying organic matter…

To be clear, Cold Spring Brook can never be returned to its natural state. In fact, we don’t know what its natural state was, or even exactly where the stream was originally located. A large scale restoration effort of what is currently there would be costly and difficult due to the extensive dredging, deep accumulation of decaying organic matter, and end-to-end straightening.

What could be done relatively easily and inexpensively, and what NFC hopes to be able to do, is some level of small scale, 100 feet or so, low-impact manual site-specific stream restoration. The idea would be to work where the stream is currently in the best shape, and where we could get what we need to work with to the water in the least disruptive way possible.

There are three 90-degree turns in Cold Spring Brook within Cold Spring Park. While the easternmost is located at the confluence of a tributary, the two westernmost turns provide some level of sinuosity to work with. There are also some downed trees that provide instream structure and some level of depth, as well as places where the stream pushes up against a stable natural bank. This is also a place where the team recently spotted a fish…

A volunteer effort involving Christmas tree bank revetment to narrow the streambed and eliminate the mud flats, large woody deposits pulled from the surrounding area, and manual channel dredging to remove some level of decaying organic matter could help create a more natural environment in parts of Cold Spring Brook. This would also increase the amount of habitat conducive to supporting fish and other aquatic life.

While NFC believes in working where it is most needed, not most visible, restoring a small section of stream that happens to be next to a popular walking trail would serve as a way to show people what Cold Spring Brook might have looked like before it was straightened, dredged, widened, and filled with decaying organic matter. It would also help improve the aesthetics of the stream and the park itself.

For NFC, waters without wild native fish where they once occurred are incomplete. After centuries of manipulating our rivers, streams, lakes, and ponds to be what we thought they should be, it’s time to fix what we broke where we can do so. Cold Spring Park is one of the most notable undeveloped public lands in the area, restoring at least some level of stream would be the icing on the cake as they say…