Projects

An interdisciplinary assessment of population growth and development impacts on the Fish River Basin coastal community

End Date: 02/1/10

Abstract

Weeks Bay, one of only three designated Outstanding National Resource Waters in the state of Alabama, is under stress due to population growth and urbanization in its watersheds. High proportions of impervious surface, typical consequence of urbanization, can lead to increased nutrient and sediment loading into streams. Urban developments have also shown to increase heavy metals, bacteria loadings, and stream temperatures. The assessment of the impact of LULC changes and build out on the quality of its major water supplier, the Fish River, is therefore of paramount importance for the future management of the Bay area.

In this research project we propose to implement an interdisciplinary approach to quantify the impact of land use/cover (LULC) changes on the water quality parameters, NO3-N, Total-P, and TSS in the Fish River Basin, and disseminate this knowledge to local community and decision makers through outreach activities to preserve and improve the environmental and ecosystem health of the Weeks Bay area. Past, present and future water quality of the Fish River watershed will be assessed through regression techniques and complex watershed-scale modeling that utilizes past observed data as well as new data that we propose to collect. This project involves adding several innovative steps to traditional water quality analysis and modeling in the Fish River Watershed. These innovations include linking longitudinal water quality analysis to geographic analysis of land use and socio-economic changes, analyzing and demonstrating land use practices that can be used by citizens, and policies that can be used by government agencies to address water quality problems. Finally, we demonstrate how a community-based, citizen-led approach to addressing water quality can create positive change for the coastal community.

A watershed scale water quality model, SWAT, will be constructed for the study area, and will be calibrated/validated by utilizing data collected more than 10 years ago. The water quality data to be collected during the course of this project will be used in post-validating the SWAT model, i.e. testing its predictive power in estimating changes in NO3-N, Total-P, and TSS owing to LULC alterations. We will develop future LULC scenarios for the watershed based on Baldwin County Planning Commission’s population projections and zoning maps for the year 2020 to appraise the future water quality of the area which could lay a ground for science based decision making for the local authorities. Best practices that can be used by both citizens and governments to address the water quality impacts will be identified. The information obtained from the water quality/modeling and best practice analysis will be used to inform a demonstration Master Plan, and will be assessed through evaluations of a charette and an educational workshop.

Results generated by this study will be helpful to communities, watershed groups, private industry, and other stakeholders working to protect, conserve or restore water quality and target outreach efforts. This information is critical as resources are tight and communities working to meet state and federal regulations need to use funds and time efficiently.

Objectives

The overall objective of this proposed research is to implement an interdisciplinary approach to quantify the impact of land use/cover (LULC) changes on the water quality parameters, Nitrogen (N), Phosphorous (P), and total suspended sediment (TSS) in the Fish River Basin, and disseminate this knowledge to local community and decision makers through outreach activities to preserve and improve the environmental and ecosystem health of the Weeks Bay area.

The specific objectives during the 1st year are:

  • To characterize the changing LULC dynamics in the Fish River Watershed over the course of the past 15 years through high resolution GIS data.
  • To collect flow and water quality data (NO3-N, Total-P, and TSS) from Fish River subwatersheds. When combined with data collected in the past, this will help us identify the linkage between water quality and LULC in the watershed. 
  • To construct the watershed-scale water quality model, SWAT, for the Fish River watershed, and calibrate and validate it with available data collected in past studies.
  • To identify the best management practices that can be used by both citizens and governments to address the water quality impacts documented in model.

The specific objectives during the 2nd year are:

  • To collect flow and water quality data (NO3-N, Total-P, and TSS) from Fish River subwatersheds. When combined with data collected in the past, this will help us identify the linkage between water quality and LULC in the watershed.
  • To post-validate the SWAT model with the new data in order to appraise its credibility in estimating the impact of LULC alterations on water quality.
  • To estimate future water quality conditions based on future build-up and LULC scenarios.
  • To educate citizens about water quality problems and simple solutions that help address those problems.
  • To demonstrate the use of low-impact landscape design strategies as a solution to water pollution.

Methodology

Year 1:
Temporal and spatial variations in LULC over the past 15 years will be generated for the Fish River Watershed from high resolution GIS. Flow and water quality data (NO3-N, Total-P, and TSS) will be collected from sites where similar data has been collected in the past in order to quantify the impact of LULC changes on water quality. The watershed scale SWAT model will be applied to the watershed, and will be calibrated based on past collected water quality data. Existing methods for improving water quality in other areas of the country with similar water quality problems (particularly costal communities) will be identified and reported to various user groups in the Fish River Basin, such as farmers, foresters, local government agencies, etc. (Best Practice Analysis).

Year 2:
Flow and water quality data (NO3-N, Total-P, and TSS) will be also be collected during the first quarter of the second project year from the same sites. The water quality data collected during this project will eventually be used in post-validating the SWAT model, i.e. testing its predictive power in estimating changes in NO3-N, Total-P, and TSS owing to LULC alterations. We will develop future LULC scenarios for the watershed based on Baldwin County Planning Commission’s population projections and zoning maps for the year 2020 to appraise the future water quality of the area which could lay a ground for science based decision making for the local authorities. The information obtained from the water quality/modeling and best practice analysis will be used in a demonstration Master Plan, and thus will be assessed through evaluations of the charette workshop.

Rationale

Weeks Bay, one of only three designated Outstanding National Resource Waters in the state of Alabama, is under stress due to population growth and urbanization in its watersheds. The assessment of the impact of LULC changes and build out on the quality of its major water supplier, the Fish River, is therefore of paramount importance for the future management of the Bay area. Pollutant data and the modeling results generated by this study will be helpful to communities, watershed groups, private industry, and other stakeholders working to protect, conserve or restore water quality and target outreach efforts. This information is critical as resources are tight and communities working to meet state and federal regulations need to use funds and time efficiently. The proposed research in this project directly falls under the Strategic Actions 4, 9, and 10 of Priority Theme Area 1, and Strategic Action 8 of Priority Theme Area 2, listed in 2006-2010 MASGC Strategic Plan.

Results

Thesis: Spatial and Temporal Trends and the Role of Land Use/Cover on Water Quality and Hydrology in the Fish River Watershed

Thesis: Modeling impact of Land Use/ Cover changes on Water Quality and Quantity of Fish River Watershed