Prior to 1996, residents of Ewing Township, N.J., endured periodic flooding and watched nervously as erosion accelerated. “I was losing a bit of my backyard every time we had a storm,” says Tula Arland, a local resident. “I was concerned that one day the stream would be up to my back door.”
Shabakunk Creek, a tributary to the Asunpink River, flows through the center of Ewing Township. Residential development surrounds the upper portion of the creek, while commercial properties surround the lower portion.
Concerns about flooding were heightened in June 1996, when a 100-year storm event delivered more than seven inches of rain in less than four hours. More than 170 residents and 75 businesses suffered damage that totaled more than $10 million. Additionally, the storm cost the township $24 million in overtime for municipal cleanup and repair.
To solve the problem, the township embarked on a flood and erosion control project along the west branch of Shabakunk Creek. The $4.2 million project brings relief to the community's 34,000 residents, as well as to business owners, and it promises to save the township money in the long run.
Determined to prevent similar economic loss and personal hardship in the future, local leaders commissioned a study that resulted in recommendations for flood control measures. Manalapan, N.J.-based Schoor DePalma performed the study, which included hydraulic modeling to identify and rank the areas affected most by bank erosion.
Modeling results provided the basis for the township's control plan, which addressed a four-mile stretch along the creek. The company then was hired to handle hydraulic and hydrologic design, environmental and construction permitting, construction management andmanagement. Because the project area included a trout run and a half-acre of wetlands, the project team had to work closely with the New Jersey Department of Environmental Protection to obtain permits.
The project team met with prospective contractors, while local leaders held public hearings to explain the control plan to residents and business owners. At the same time, residents learned that the project would be financed with a 20-year, low-interest loan from the New Jersey Environmental Infrastructure Trust.
Over the course of a year, C & L Contracting, based in Bridgewater, N.J., implemented the flood control measures. It built three basins upstream of the flood area; installed two-and-a-half miles of interlocking concrete blocks in areas whereflow was fastest; and planted vegetation in low-velocity areas. It cleared the streambed of silt and debris, and, finally, it mitigated the wetlands disturbance by planting wetlands vegetation and 400 trees along the newly constructed banks.
In addition to paying for the engineering, construction and construction administration, the loan covered the costs of two property purchases, as well as the cost of new equipment. Small back-hoes and dump trucks are used by the localdepartment to maintain the project area.
The project's completion has had an immediate effect, says Randy Martin, owner of a local auto service business. “Flooding always had an impact on the business district. In 1996, I was out of business for 13 days,” he notes. “These improvements have allowed us peace of mind. We can operate without fear of major financial loss.”
Local leaders are hopeful that the Shabakunk Creek project will be the catalyst for surrounding communities to implement similar flood and erosion controls. According to Ewing Township Mayor Alfred Bridges, regional improvements could save millions of dollars during the next major storm event.