As the dam was nearly 100 years old, it had many deficiencies, including inadequate spillway capacity, embankment instability, limited reservoir capacity, spillway concrete spalling damage, spillway slab cracking, limited access, and inadequate public safety features. Flyway Excavating worked to modify the Milltown Dam to bring it up to current compliance standards, preserve and restore natural flow regimes to the stream and reservoir, and enhance the ecological balance of Chester Creek.
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In addition to upgrading the dam to meet compliance standards and safety regulations, PADEP also required that Chester Creek, the waterway on which Milltown Dam is situated, be allowed to reestablish a natural course across the site. Thus, the Milltown Dam Park Open Space Master Plan was developed, with the following project goals outlined.
- Develop a management plan for the stream
- Monitor stream banks for erosion and repair as soon as possible.
- Stabilize the stream to prevent head cutting of the culvert at East Strasburg Road and into the wetlands through use of riffles or step pools.
- Preserve and enhance existing wetlands, maintaining hydrology as close to existing conditions as possible.
- Restore habitat connectivity through improved fish passage and habitat restoration.
- Protect and preserve the privacy of adjacent and nearby residences through proper setbacks, screening, and other techniques.
- Create ponds to allow for open water views from neighboring homes and adjacent roads.
The Milltown Dam project sought to benefit the surrounding neighborhood by reducing the risk of stream and reservoir flooding, improving the water quality and ecological systems, and providing a community destination for passive recreation.
Flyway’s Involvement
Flyway contributed significantly to the Milltown Dam renovation project, leading key modifications that included:
- Lowering the main spillway
- Extending the training wall on the right side of the existing spillway
- Installing riprap upstream and downstream of the spillway
- Removing the upper portion of the control tower
- Filling the lower control tower vault with flowable fill
- Lowering the right embankment eight feet
- Placing the concrete spillway and core wall
- Installing the articulated concrete block armoring on the downstream face of the embankment
- Stabilizing disturbed areas of the site
The Result
The Milltown Dam is now compliant with PADEP dam safety regulations and no longer poses a safety threat to neighboring properties. Now that the dam modification work is complete, East Goshen Township has been able to pursue grant opportunities to develop additional recreation features at Milltown Dam Park, such as the creation of a 2.5-acre stocked pond, 0.7 miles of paved and unpaved trails, two ADA-accessible fishing piers, an ADA-accessible 20-space parking lot, and a pavilion and plaza.