With the recent heavy rainfall this week, floodplain restoration and natural features like wetlands (known as green infrastructure) are proving to have an obvious impact on flood reduction. Regional solutions, such as floodplain restoration, inherently decrease impacts that extend beyond a single parcel of land. Reduced flooding and improved water quality are generally observed downstream as well and include the protection of infrastructure such as roads, bridges, homes, and businesses.
Here are three green-infrastructure projects that are making a real difference in Lancaster County.
Within the past few years the Lititz Borough Flood Committee completed a streambank stabilization of Lititz Run and recently created floodplain wetlands along the stream. The project is located upstream of the North Oak Street Bridge. You will see from the video footage taken on July 26 this project allows the rain water to be dispersed into the floodplain. In doing so, much of the water’s energy is dissipated, protecting the bridge and other infrastructure along the stream valley from excess flow damage. Also, it helps to filter out sediment and nutrients, reducing pollution and improving water quality of Lititz Run.
A 17-acre floodplain restoration project at Rock Lititz located in Warwick Township restored 3,136 linear feet of Santo Domingo Creek by removing sediment from the valley bottom and increasing floodwater storage potential. The project helps to reduce stream bank erosion and promotes the infiltration and filtration of runoff resulting in water-quality benefits. The increase of flood storage, and the resulting peak-rate reduction benefited the property owners by eliminating the need for traditional stormwater basins and increasing the amount of usable space for development. The township and neighboring borough benefit from the regional green infrastructure project with a reduction of flooding downstream and increase in water quality.
To meet stormwater-management requirements for a phased land-development project, an 11.5-acre floodplain restoration was completed on Brubaker Run in East Hempfield Township. It restored 4,750 linear feet of stream length and 8.4 acres of wetlands and native plant communities were created. The benefits include flood reduction, enhanced groundwater recharge, pollutant reductions, and significant ecological and aesthetic improvements. This restoration approach exceeded the stormwater management requirements of the development, but also helped East Hempfield Township meet its MS4 Chesapeake Bay pollution reduction goals at no cost to taxpayers.