Lake Minnewaska Terrain Analysis

Background

In 2014, Pope Soil and Water Conservation District (SWCD) began an effort to strategically locate best management practices (BMPs) using GIS-based water quality analysis. The SWCD retained HEI to perform the terrain analysis.

The Project

Recently, HEI finished the groundbreaking project that used advanced geographic information systems (GIS) techniques to assist the SWCD in restoring and protecting water quality in Lake Minnewaska. The published report also features terrain analysis standards developed to add value to the District’s project.

The project identifies areas contributing relatively high amounts of sediment and nutrients downstream and and also finds potential locations for BMP implementation based on the landscape, land use, and loading data.

The project report includes extensive documentation of provedures to protect the investment made in the project. The enhanced geospatial water quality products (EGWQP) developed during the project are standardized and consistent with other state-funded water quality initiatives. The report also defines the level of digital elevation model (DEM) conditioning that took place. Every EGWQP product created is listed and described in the report’s Appendix.

Following the analysis, HEI’s team presented the information in a knowledge-sharing workshop for Pope SWCD staff.

HEI completed the following tasks:

• Reviewed previously completed conditioned DEM model and incorporated updates into the conditioning process.
• Performed an analysis to determine areas not contributing runoff downstream during a specified rainfall event representatitve for water quality analysis.
• Created enhanced geospatial data products including the stream power index (SPI), revised universal Soil Loss Equation (RUSLE), and Total Phosphorus (TP) and Total Nitrogen (TN) loading estimates.
• Created prioritizations for BMP implementation at both field and subwatershed scales.
• Performed an analysis to predict suitable locations to place common water quality BMPs.
• Prepared a detailed report summarizing methodologies and data inputs and outputs.
• Conducted a workshop to give staff hands-on guidance to practically apply the enhanced geospatial water quality and prioritization
  products.