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Headwaters Summary Analysis

Cooley Brook’s headwaters are tucked behind the active recreation areas in Bliss Park and form a distinct boundary between two different character zones of the park: the active recreation areas catering to young families at the playground or ballfields, and neighborhood dog walkers and hikers who use the trails to the north.

The active recreation areas, consisting of a swimming pool, a celebrated boundless playground, ballfields, a basketball court, and a tennis court, have a different character than the rest of Bliss Park or Laurel Park. This is the largest cleared and developed area in the parks and, with three parking lots, often provides self-contained entertainment for park-goers. Though Cooley Brook is only about 60 feet into the woods from the edge of the ballfields, most of the people who visit these more programmed areas are not aware of the brook’s existence. And since the channel is deeply incised in Bliss Park, the active recreation areas are largely protected from a 100-year flood. Though there are no easy access points to Cooley Brook, informal paths leading to the brook and overlooking it on the north side show the desire to have more interaction with the stream.

However, the deeply eroded and unstable banks are a huge limitation for human / stream interaction. Additionally, the informal path to the brook is in the same location as a concentration of the most intense erosion sites in the brook system. Road runoff directly entering the stream also decreases the appeal of human / stream interactions here.

There is also no mechanism to slow water entering the channel, which compounds the erosion issue and creates a stream channel disconnected from a floodplain by forming steep banks without terraces. However, the largely intact forest ecosystem with little to no invasives pressure provides great habitat and ecosystem benefit.

HEADWATERS : SPREAD THE WEALTH

Taking advantage of existing landforms, this design goes to the extreme in its attempt to decrease the amount of water in Cooley Brook by separating the stormwater pipe inputs into two channels. It also asks the question, What other human / stream connections exist besides physical access to the water?

hydro-ecologIcal changes

• The forest northwest of the swimming pool is replanted with tree and shrub species to block access to the stream where there is intense erosion.

• Meadow species planted between the swimming pool and the all-persons trail also discourage access to the intensely eroding area, while increasing habitat and decreasing maintenance.

• Rain gardens along the southwestern edge of the active recreation areas infiltrate and clean water before it enters the brook.

• A biodetention basin is constructed in the existing eastern parking area to allow for the southeast stormwater line to daylight earlier; the road is blocked off except for maintaining the biodetention basin.

• A biodetention basin is constructed where the eastern stormwater line enters the park, creating a new wet area and reactivating an ephemeral stream channel that eventually rejoins the Cooley Brook (see sheet 29).

The Human Element

• An all-persons trail in the woods northwest of the active recreation areas connects the existing paved trails to the trails in Laurel Park, with a crosswalk on Laurel Street. This trail includes a small viewing platform over the brook and relocates nature play from northwest of the pool to this area.

• Two viewing platforms, one connecting to the existing paved trail and one connecting to a new all-persons trail, provide views of the brook and also encourage exploration of the forest north of the ballfields.

• The currently unused building east of the ballfields is taken down and its footprint is reused for new parking to replace the eastern parking lot that is lost.

• Another all-persons trail connects the new parking lot to the viewing platforms and Oakwood Drive, bringing people past the biodetention basins.

Pros

• Reduces the volume of water in the main stem of Cooley Brook, reducing its erosive power.

• Treats stormwater runoff before emptying it into the brook.

• Blocks off access and revegetates the area with the most intense erosion.

• Addresses puddling issues near the playground, parking, and basketball court.

Cons

• Little to no opportunity for humans to touch the stream and limited viewing opportunities.

• New wet areas may change the experience of the hiking trails.

• Requires stormwater pipes to be excavated and relocated to gain appropriate elevation for biodetention basins.

InstallatIon / maIntenance

• In order to have water empty into a biodetention basin that is near ground level, the stormwater pipes will have to be dug up and reset at a higher elevation from the nearest catch basins.

• Biodetention basins and forebays will require periodic maintenance.

• Once established, the meadow and new plantings should need little (yearly) maintenance.

Conceptual Design Details 5

Not enough is known about stormwater flows to predict how much water will enter the new stream channel shown in the Spread the Wealth design. Based on contour and elevation data, the water would approximately follow the dashed blue line (shown to the right) and eventually join a tributary of Cooley Brook. There is a depression in the middle of this route, meaning water would likely pool here, infiltrate into the soil, and continue to flow as groundwater except during large storm events, when the water would have to flood a larger area before the grade would allow it to continue draining towards Cooley Brook. At this time, it is impossible to know whether water would be flowing here all the time or only during large storm events. If flows are perennial, up to four new boardwalks or bridges would be needed for the trails in this area. More research is needed to determine the feasibility of this design element.

Re-routed trails

Potentially floodable area before water continues draining

Proposed pipe outfall; regrade around outfall

Approximate route of water based on contour data

Stormwater pipes coming off Oakwood Place

HEADWATERS : BRIDGE THE GAP

How close can people get to the stream while maintaining stream stability, increasing stormwater infiltration, and increasing ecological health? Bridge the Gap improves the human connection between the active recreation facilities and Cooley Brook.

hydro-ecologIcal changes

• Bioengineering strategies such as fabric-encapsulated soil lifts and live stakes are used to stabilize the stream bank where the most severe failures exist.

• A grass-dominant meadow borders the swimming pool, visually softening the stark chain link fence and creating a sense of mystery as it sweeps the woodland edge.

• Small rain gardens are sited to reduce flooding of programmed park spaces.

• Storm drains are daylighted into two biodetention basins. Step pools are constructed from biodetention basin spillways to the stream channel to reduce runoff velocity down the slope and mitigate erosion.

The Human Element

• A natural play area along the wood edge provides a more programmed and defined space, concentrating use away from eroding stream banks and connecting a new trail on the southern ridge of Cooley Brook to the park.

• A bridge is built to improve circulation and connection between the existing park amenities and brings people closer to the stream.

• An all-persons trail connects the existing ADA path with a new loop through the forest, crossing the stream at a rest area with interpretive signs about watershed and stream restoration in Cooley Brook.

• Existing ADA paths are reconfigured to improve circulation and create tempo in the walking experience, passing a picnic and seating area along the wood edge.

Pros

• Stormwater is slowed, captured, and infiltrated before entering the brook, reducing its quantity and velocity.

• New trails and bridge improve site-wide circulation, create a connection between the forest and programmed park spaces, and improve human access to the stream.

• Stormwater infrastructure is celebrated as a visible feature of the human experience in the park, accompanied by interpretive signs to explain the importance of Cooley Brook as a natural and recreational resource.

• Comfortable seating/rest areas are defined and enhanced.

• The structural landscape features are softened with abundant vegetation.

Cons

• Increased access to the stream will bring more use and disturbance of the stream system.

• Daylighting the stream upslope will require technical engineering and construction, with the scope of potential impact reaching Bliss Road and Oakwood Drive.

• Removal of mature trees will most likely be necessary, but can be mitigated with a Tree Save Plan, a process of identifying trees to save and strategies to protect them during construction.

• Installation will require tree removal, excavation of the Bliss Road parking lot, and disruption to park programming.

• Biodetention basins and the meadow will require seasonal maintenance.

• During installation,most of the all-persons trail should be graded to a less than 5% running slope.

• Bioengineering strategies including fabric-encapsulated soil lifts, step pools, and live stakes will require technical design and installation

escarPment steP Pools cross vanes

faBrIc-encaPsulated soIl lIfts (fesl)

Regional Dam Removals

Dams are a common sight in Massachusetts, being used historically to power small mills or meet municipal water needs. With over 3,000 dams in the state (most of which date back to the 1700s), and with the knowledge that dams cause serious ecological disconnection and degradation, the state is reckoning with how to remove many of them.

Massachusetts’ Division of Ecological Restoration (DER) works to remove dams and restore river processes, as well as update culverts for increased aquatic connectivity. The DER has approximately 350 dam removal projects, about half of which are complete and half are in-progress. These projects, ranging all over the state from large dams on major rivers to small ones on tributary brooks, create good company for Longmeadow’s Cooley Brook revitalization project (Division of Ecological Restoration).

Precedent: Bartlett Pond Dam Removal

Prior to removal, this dam’s condition was highly deteriorated and created a serious hazard for a Route 117 bridge. Removing the dam in 2014 addressed that hazard and reconnected 18 miles of Wekepeke Brook, increasing brook trout habitat and tributary connections (Division of Ecological Restoration, Bartlett Pond). Similar to the Cooley Brook project, the goals of the Bartlett Pond dam removal included:

• Restoring habitat connectivity

• Improving water quality

• Eliminating risks and liabilities associated with a hazard dam

Precedent: Abbey Brook Revitalization

Just north of Longmeadow, another dam on another tributary to the Connecticut River, also located in a public park, is slated for removal. Abbey Brook begins in a forested wetland and flows past two dams in Szot Park before entering the Chicopee River and subsequently the Connecticut River. Though other dams on the Chicopee will limit aquatic connectivity from the Connecticut to Abbey Brook, this project will allow 1.5 miles of the brook to flow free. When the Town found out the dams were in poor condition and needed to either be removed or repaired, it recognized the opportunity to restore more natural conditions to the brook through dam removal. This process is in the public engagement and permitting phase, with grants awarded from DER and other sources (Geosyntec Consultants, 3).