The Watershed Atlas Project
Brian Lee, Department of Landscape Architecture
Corey Wilson, Department of Landscape Architecture
Collin Linebach, Department of Landscape Architecture
Drew Heering, Department of Landscape Architecture
Landscape Characterization in Kentucky as an Indicator of Watershed Health
Assessing the landscape from a watershed and waterway health perspective provides an indication of the quality of an area's land management decisions. The Watershed Atlas Project is an approach to waterway and watershed health assessment that utilizes existing publicly available geospatial data (Kentucky Geography Network and related sites) to visualize landscape indicator aspects of multiple watersheds simultaneously. Initial grounding for this work can be found in An Ecological Assessment of the United States Mid-Atlantic Region: A Landscape Atlas (1997) and has been modified and expanded for The Watershed Atlas Project. By looking at landscapes as indicators to infer watershed health, it is possible to modify land management decisions for the future to improve water quality and reduce the risk of future threats, and understanding how watersheds are statistically similar or different (cluster analysis) can aide in mobilizing a suite of protection or mitigation strategies.
The Watershed Atlas Project uses the Hydrologic Unit Code (HUC) as the fundamental unit of analysis. HUC-14s are the smallest unit of the United States Geological Survey's (USGS) hierarchical organization scheme for cataloging watersheds across the United States from the largest scale drainage basins in the nation, down to the smallest scale watersheds (The National Atlas, 2007). With this atlas, watersheds are characterized using data available from the Kentucky Geography Network in the Environmental Systems Research Institute's (ESRI) ArcGIS environment. ESRI's ModelBuilder was utilized with additional data (Clumpy Index) reported from Fragstats to measure the landscape according to more than 50 indicators (currently), organized by theme: Geographic, Geomorphic, Human, Vegetation, Riparian, and Specialty Indicators. The atlas provides a series of maps illustrating relationships among watersheds for each indicator as well as a detailed data table providing numeric values for each HUC and each indicator.
To date, The Watershed Atlas Project has been utilized to predict watershed health in the Licking and Kentucky River Basins, as well as for a seven Kentucky county region, including: Clark, Fayette, Jessamine, Madison, Owen, Scott, and Woodford counties; and an effort to assess the Licking River Basin in its entirety is currently underway. Students in the capstone Service-Learning Studio have applied elements of The Watershed Atlas Project to Boone, Campbell, Kenton, and Logan counties.
Next steps for the Watershed Atlas will work toward applying the data to on-the-ground approaches for protecting or improving watershed health. One approach to that process includes identifying priority watersheds in which to focus efforts. Watershed Atlas data are used to prioritize watersheds through a process which calculates a Z-score for several key landscape indicators which can be added and weighted based on areas of interest. A Riparian Agriculture scenario, for example, might weight the Riparian Agriculture indicator Z-score very high, at 85%, and include the Road/Stream Intersections, Stream Density, and Riparian Zone Slope indicators at 5% each to determine those watersheds which are high priority due to known watershed health issues related to waterway and riparian interactions with agricultural practices.
Water Quality Trading in the Kentucky River Basin
Aspects of the Watershed Atlas are being used to provide several types of geospatial analyses to a project by the University of Kentucky Department of Agicultural Engineering researching Water Quality Trading Opportunities for the Kentucky River Basin. The Watershed Atlas, in addition to two different versions of the Soil and Water Assessment Tool (SWAT), is being utilized to indicate where Nitrogen and Phosphorus emission credit is needed and where the credit potentially exists in the river basin. It is important to understand how the two nutrients behave in the Kentucky River Basin so that a more realistic spatial trading market could be explored for feasibility. For Landscape Architecture, this project is particularly important because it reinforces the linkages between the urbanized and rural areas of the state while integrating natural and social systems that have implications for how thousands of acres of the state might look one day.