Grantee Research Project Results
Final Report: Valuing Water Quality Improvements in Heartland Reservoirs
EPA Grant Number: R840467Title: Valuing Water Quality Improvements in Heartland Reservoirs
Investigators:
Institution:
EPA Project Officer:
Project Period: September 1, 2022 through May 10, 2025
Project Amount: $740,014
RFA: Water Quality Benefits (2022) RFA Text | Recipients Lists
Research Category: Water Quality , Water
Objective:
To provide willingness to pay (WTP) estimates for water quality improvements and aquatic resources in Midwest reservoirs.
Summary/Accomplishments (Outputs/Outcomes):
We created water quality models for three Midwest reservoirs; Marion reservoir in Kansas, and Table Rock and Lake of the Ozarks in Missouri, USA. We supplemented publicly available water quality data with our own data collection efforts, including high frequency water quality monitoring buoys on Marion and Table Rock Lakes. We coupled watershed (SWAT+) and lake (GLM-AED models) to accurately predict water quality parameters in our three study reservoirs. Following calibration of the paired watershed and lake models to observed climate and hydrological inputs, a series of scenarios was developed and run in to represent the following water quality management practices: (1) a reduction in point source nutrient loading; (2) adoption of improved grazing practices in which cattle were excluded from riparian areas; and (3) a combination of both point source load reductions and riparian grazing exclusion. The resulting streamflow and nutrient loads from these water quality management scenarios were then inputted to the lake model to establish the inflow boundary conditions. Relative differences in chlorophyll-a (a proxy for phytoplankton biomass) and Secchi depth (a proxy for water transparency) estimates were used to establish probable shifts in the magnitude and frequency of water clarity indicators for informing the Willingness to Pay (WTP) surveys for each of the study reservoirs. This coupled linkage from watershed model to lake model to WTP survey was completed for Table Rock Lake; however, due to the stop order, the coupled models for Lake of the Ozarks and Marion have been developed but not fully calibrated, and the linkage to the WTP surveys is not complete.
The coupled models for Table Rock Lake informed a choice experiment survey of visitors to Branson, Missouri, which is a submitted manuscript with the Journal of Agricultural and Resource Economics. The survey demonstrates how valuation can be derived for waterbodies where population density is low. In particular, the waterbodies that we study are recreational reservoirs where traditional survey methods are costly. We present an approach to the valuation of water quality improvements that are heavily used by non-local tourists. The results compare lake users to non-users, finding no statistical difference between the two. The results highlight diminishing WTP estimates as water quality improves. Finally, the results highlight the impact the taxing agency, and therefore payment vehicle, has on valuation estimates. Building on the Table Rock survey, we analyzed the market extent for water quality improvements in Table Rock Lake. A working paper has been developed and is expected to be submitted for publication. Two additional surveys of Lake of the Ozarks and Marion Lake reservoirs were developed and will provide market extent analysis based on visitor location and preferences.
In regards to water quality valuation, lakes and reservoirs in the Environmental Protection Agency’s (EPA) Great Lakes Region 5 are notably understudied. This gap in valuation estimates leads to difficulties in benefits estimation for state and federal agencies concerned with cost- benefit analysis. This is particularly impactful for water quality improvement projects affecting recreational reservoirs. The results of this project’s survey and analysis deliver WTP estimates for benefit transfer researchers for similar recreational reservoirs.
Journal Articles:
No journal articles submitted with this report: View all 2 publications for this projectSupplemental Keywords:
Watershed, Water Quality, Climate, Landcover/management Change, Integrated Model, Community-based, Preferences, Socio-economic.Relevant Websites:
North Mizzou Limnology Lab Exit
Progress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.