Dr. Merritts observing a steep bank of sediment built up behind a milldam in MD


PUBLIC PROJECTS
Pennsylvania NRCS Conservation Innovation Grant 4: 2025-202
Pennsylvania NRCS Conservation Innovation Grant 3: 2022-2025
***in progress*** Proposal Abstract: The primary goal of the project is to identify and promote legacy sediment (LS) repurposing opportunities in abandoned mine land (AML) reclamation. These opportunities include the identification of commercial and retail product markets and the establishment of a Sediment Management System (SMS) framework to promote LS reuse. LS repurposing will require a coordinated effort to engage stakeholders in the project. Establishment of a working group of public and private stakeholders is a central project objective. Additionally, we plan to identify and confirm existing and potential incentives for landowner and stakeholder participation. Items to be considered are the valuation process for donated land and soil tax benefits, landowner partnership agreements, social motivations, and cash payments for soil and land rights. Project deliverables include a LS Consumer Benefit Statement and the SMS framework. The LS Consumer Benefit Statement will describe LS origin, chemistry, and uses. Development of the SMS framework will promote LS repurposing by matching project supply and demand through transparent pricing, soil quality, soil quantify, and location datasets. The SMS platform will be of original design or modification of an existing platform.




PA DEP Growing Greener Grant 2: 2021-2025
***in progress*** Proposal Abstract: This project will continue the work of Water Science Institute on the field and policy review of the effects of dam removals on water quality in Lancaster County. This will assist the Lancaster Clean Water Partners and other stakeholders in the implementation of the Pennsylvania WIP. Lancaster, as a designated Tier 1 county, has been requested to reduce nutrient and sediment loads to account for 21% of the Commonwealth’s TMDL. A significant part of the county stakeholders emerging strategy is to address the issue of legacy sediment and the implications of high nutrient and sediment loads associated with the removal of historical milldams. Better understanding and coordination of dam removal policies and protocols is seen as an important component of Lancaster’s overall program to support the Pennsylvania Chesapeake Bay Requirements. Deliverables will include proposed methodology for forecasting the impacts of dam removal and recommend protocols for maximizing environmental opportunities associated with dam removals. Refined forecasting techniques will promote greater coordination between state, county, and local officials and organizations regarding dam removal and how the benefits of the practice can be enhanced, and unintended consequences minimized. Lastly, the project will advocate the use of WSI mapping products in Lancaster County for identifying and targeting existing and proposed dam removals for maximum restoration benefits.




NFWF-LCWP Creschendo in Collaboration: 2020-2024
Final Report Abstract: The Crescendo in Collaboration program within the Lancaster Clean Water Partners (LCWP) sought to bring together a diverse group of organizations with the goal of using data driven strategies for targeting impactful restoration projects in Lancaster County. WSI's role in the program was to use our innovative mapping techniques for identifying high potential stream restoration sites. The county-wide datasets we created were incorporated into the LCWP's Collaborative Watershed Mapping Tool, including historic milldam location, the 2019 Lidar dataset, stream bank erosion polygons (2014-2019), legacy sediment terraces, and several hotspot maps identifying where the most bank erosion is occurring along streams in the county.
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Virginia NRCS Conservation Innovation Grant: 2020-2022
Final Report Abstract: Smith Creek watershed (VA) was identified as a showcase watershed for the Chesapeake Bay in 2010, and since, has been the site of numerous BMP projects and scientific studies. Recent studies have concluded that stream bank erosion of legacy sediment is the primary source of suspended sediment, and associate nutrients, in the watershed. Since repeat Lidar was not available for watershed-scale wide DEM differencing, unlike our previous Pennsylvania projects, the team utilized our UAV structure-from-motion/photogrammetry methodology to measure stream bank erosion rates at several sites. We also mapped all legacy sediment terraces and historic milldam locations in the watershed.


WSI Specialists Logan Lewis and Sam Feibel stand in front of a well-preserved mill building at Sellers' Mill in Mauzy, VA. Logan and Sam used drone photogrammetry to create a digital elevation model of the eroding Legacy Sediment terraces upstream of the breached dam.

Logan Lewis starts a drone flight at Bruce's Mill on Virginia's Smith Creek.

Rows of trees lining the old mill race are visible in this aerial drone shot of Sellers' Mill. The wide Legacy Sediment terraces formed behind a since-breached dam now serve as pasture for cattle.

WSI Specialists Logan Lewis and Sam Feibel stand in front of a well-preserved mill building at Sellers' Mill in Mauzy, VA. Logan and Sam used drone photogrammetry to create a digital elevation model of the eroding Legacy Sediment terraces upstream of the breached dam.
PA DEP Growing Greener Grant 1: 2018-2022
Earlier research by WSI and our partners at Franklin & Marshall College had identified historical milldam locations throughout Lancaster County, several of which are still intact. Our research primarily focused on the Chiques watershed, where four milldams were removed between 2014-2019. We extensively monitored Krady milldam pre/post removal using bathymetry, bank edge surveys, game camera photos, soil samples, and water quality measurements. Other recent removals and intact milldams were also visited and documented. This project led to the alternative analysis for the future Roller milldam removal and the WSI/SRBC hosted Pennsylvania Dam Removal Forum (link?).



Krady Mill Dam, located in Lancaster County, PA, is removed in July, 2018.


Pennsylvania NRCS Conservation Innovation Grant 2: 2018-2020
The goal of this project was to expand on our original legacy sediment mapping project, in Lancaster county, to six additional counties in Pennsylvania (York, Adams, Lebanon, Cumberland, Dauphin, and Franklin). Mapping includes historic milldam locations, stream bank erosion polygons (generated from Lidar DEM differencing), legacy sediment terrace locations (and sediment volumes), canopy height models (CHMs), and stream bank erosion hotspot BMP targeting maps.

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USDA NRCS Conservation Innovation Grant 1: 2016-2018
As a result from the Big Spring Run (BSR) wetland restoration project, this project helped expand on the need for additional information related to legacy sediment in Lancaster county. We developed and refined methodologies using high-resolution LiDAR DEM to locate, quantify, and prioritize legacy sediment stream bank erosion sites. From our erosion hotspot mapping and data from BSR, we examined the cost effectiveness of legacy sediment removal and wetland restoration compared to other common BMPs for nutrient and sediment reduction. Lastly, we began researching potential uses of excavated legacy sediment to offset restoration costs.

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The Water Science Institute thanks NRCS, the Steinman Foundation, and National Science Foundation grants 1451586 and 1451562 for their financial support of this study.