Bellevue Park Ponds Smart Stormwater Retrofit and Historic Enhancement

Capital Region Water
Jacobs Engineering Group
Landstudies, Inc
Bellevue Park Association
Opti by Aliaxis
Shiloh Paving & Excavating, Inc.

The purpose of this project was to implement pond retrofits on two historic man-made ponds to improve water quality, optimize the ponds for stormwater management, provide safe conveyance for extreme events, and improve ecological benefits of the ponds, while respecting the historical characteristics of the surrounding community of Bellevue Park. Bellevue Park is a landscaped neighborhood in Harrisburg, PA designed in 1909 by Warren H. Manning as part of the national City Beautiful movement. The neighborhood design includes open space “reservations,” with two connected ponds known as the Willow and Spruce Ponds. The ponds were experiencing impacts to aquatic habitat from stormwater and its associated sediment and pollutant loading and were heavily silted with eroding banks, and in need of restoration.

The implemented pond retrofit included grading to increase storage capacity, a large pretreatment device to protect water quality, modification of the pond outlet structures and spillways, and improvements to the landscape to support ecological functions, stabilize the pond banks, and improve aesthetics. The project included continuous monitoring and adaptive control (CMAC) systems to maximize storage volume capacity and control outflows from the ponds to provide optimal wet weather flow reductions to the combined sewer system operated by CRW. The system exceeds regulatory retention requirements while maintaining water surface elevations in the ponds and free surficial discharge over the restored pond spillway as desired to match the historic aesthetic of the ponds, while providing CRW flexibility to modify discharges from the ponds as needed to adapt to future changes in the watershed.