Conewago Creek Restoration Project

As The Conewago Creek Restoration Project is still a work in progress, this presentation is also a work in progress. Please continue to check back for funding updates, construction progress and water quality results.

It is Londonderry Township's hope to use this presentation to communicate project progress with our residents, inspire municipalities and non profits to take on similar projects, and attract funding opportunities.

Please email Monique Dykman, Londonderry Township MS4 Environmental Specialist, at  mdykman  @londonderrypa.org  with any questions regarding the project.

The EPA and DEP enforce the  Municipal Separate Storm Sewer System (MS4)  Permit Program in communities with pockets of dense population, as determined by the census. This program requires each MS4 community within the Chesapeake Bay drainage area to implement a Chesapeake Bay Pollution Reduction Plan (PRP). The Susquehanna River contributes approximately 50% of the freshwater to the Chesapeake Bay - a highly regulated water body. The Conewago Creek is a tributary to the Susquehanna River, so any MS4 permitted community in its watershed must create and implement pollution reduction projects as part of their PRP to reduce existing sediment loading in their MS4 planning area by 10%. These project must be completed by September 30, 2023 and are an unfunded mandate placed on MS4 permittees.

For the 2018-2023 MS4 permit cycle the PRP requires a 10% reduction in total suspended solids for MS4 communities in the Chesapeake Bay drainage area, which both Londonderry Township and Mount Joy Township are. They have decided to partner together and fulfill these commitments to the Conewago Creek via the Conewago Creek Restoration Project.

There are many practices that are used in watershed restoration. One very useful practice, to municipalities, is called stream restoration, whereby streambanks are stabilized, floodplains are restored and natural stream functions are repaired.

Stream restoration projects have the potential to provide major sediment reduction benefits, at a reasonable cost. However, stream restoration cannot be fully effective if the restoration only addresses one side of the stream. Therefore, Londonderry and Mount Joy Townships partnered together to restore both the stream banks.

• Floodplain—The lands adjoining a river or stream that have been or may be expected to be inundated by flood waters in a 100-year frequency flood. 

•  Floodplain Restoraiton  is the process of fully or partially restoring a river's floodplain to its original condtitions before having been affected by the construction of levees (dikes) and the draining of wetlands and marshes. The objectives of restoring floodplains include the reduction of the incidence of floods, the provision of habitats for aquatic species, the improvement of water quality and the increased recharge of groundwater.

• Legacy Sediment (Definition by PA DEP)- Sediment that was eroded from upland areas after the arrival of early Pennsylvania settlers and during centuries of intensive land uses; that deposited in valley bottoms along stream corridors, burying pre-settlement streams, floodplains, wetlands, and valley bottoms; and that altered and continues to impair the hydrologic, biologic, aquatic, riparian, and water quality functions of pre-settlement and modern environments. Legacy sediment often accumulated behind ubiquitous low-head mill dams and in their slack water environments, resulting in thick accumulations of fine grained sediment that contain significant amounts of nutrients.

When multiple municipalities collaborate to reduce pollution, they can complete larger and more impactful projects for a lower unit cost and individual project cost. They can pool their resources to achieve economies of scale on certain fixed costs, which will allow the project to address more stakeholder and resource needs.

This project will not only cross municipal boundaries, but also county lines. In this respect, the project will address more holistic needs of the stream, and leverage a greater pool of resources. By combining the existing resources across boundaries, Londonderry and Mount Joy Townships have created a greater opportunity to solve a number of issues related to water quality, habitat creation and local recreation.

•  Londonderry Township, Dauphin County : Lead in project grant funding, scoping, engineering, grant applications, elected official support (state level), meeting scheduling, project direction, partnership development, accounting
•  Mt. Joy Township, Lancaster County : Project funding/planning, grant applications
•  The Conewago Creek Initiative :  In kind services, technical guidance, scoping, grant applications
•  Greening the Lower Susquehanna : Technical support, community relations
•  Penn State University Agriculture & Environment Center :  Long-term partner of Township, project scoping, grant application for NFWF and Growing Greener, project site identification, Water Quality Monitoring.
•  The Dauphin County Conservation District : Technical guidance, water quality sampling
•  The Lancaster Count Conservation District : Technical guidance, water quality sampling
• Private landowners and farmers: Access to private land for project installation
• Department of Environmental Protection: Funding, technical guidance, permitting

 Herbert, Rowland & Grubic, inc 

 LandStudies, Inc.  

Visit TCCCA's  website  for a detailed description of some of the projects!

A huge thank you to all of our partners, without whom this project would not be possible.

Please check this website for construction, funding, and eventually water quality improvement updates!

And lastly, huge thank you, to you - the reader - for your interest in the Conewago Creek Restoration Project.