The REMAP project aims to assess the overall hydrologic stability of sub-watersheds and link the ecological condition of the watershed sub-components (upland and riparian areas and streams) conditions within the rangeland watersheds. The long-term goal of this proposal will be to help managers understand the cause of environmental degradation and the location of potential problem areas within these watersheds. This research should improve the allocation of resources by providing greater insight to the identification of problem areas and determining linkages between these areas and stream sites.Our efforts will focus on the interrelationships between upland and riparian hydrologic stability and cumulative stream condition in a watershed. Upland conditions can be tied to stream condition at downstream (or downslope) sites through advanced flow path modeling (e.g. TOPMODEL) available within a Geographic Information System (GIS). Riparian corridors also will be evaluated by examining the potential of these areas to act as a sink and/or source area for non point source (NPS) pollutants. Information will be collected at three levels: watershed, hillslope and stream channel. This hierarchical sampling strategy will allow data to be aggregated and interpreted at different spatial scales. However, this strategy also will provide an assessment of the functionality of the different components of the watershed.
The proposed research will be divided in two phases. The first phase (year one) will focus on developing the monitoring protocol and evaluating linkages attained from flow path models. The second phase (year two) will test the monitoring protocol on different watersheds to ensure effectiveness.
Project Goal
The goal of this research is development of appropriate sampling strategies and modeling techniques that will allow land managers to assess overall watershed conditions and relate conditions in upland and riparian environments to measures of stream conditions.Research Objectives
In order to achieve the project goal, we have identified five basic objectives. The objectives are aimed at determining the condition of uplands and riparian areas within rangeland watersheds and evaluating the utility of erosion prediction and flow path models to describe potential linkages between upland, riparian, and stream conditions.OBJECTIVE 1: Determine the condition of the upland, riparian and stream conditions of sub-watersheds in the target watersheds.
OBJECTIVE 2: Examine the utility of the Water Erosion Prediction Project (WEPP) model for evaluating NPS sediment production and existing hydrologic stability of selected watersheds with varying rangeland conditions.
OBJECTIVE 3: Evaluate indices of upland and riparian sites that will facilitate interpretation of stream conditions in a watershed.
OBJECTIVE 4: Identify the nature of linkages between upland, riparian, and stream monitoring within selected sub-watersheds through flow path modeling.
OBJECTIVE 5: Ensure the monitoring protocol, linkages and models developed here can be used to assess the watershed and ecological conditions of independent watersheds.
Relevance of Project (within EPA Region)
Interest in protecting and restoring watersheds in the semi-arid and arid west has been on the rise. Most of the interest has been spurred by concern over ecosystem function and water quality, as well as loss of habitat and damage to fisheries that occur with loss of western riparian systems and degradation of streams. As impacts to these systems has increased, so has interest in their functions in flood attenuation, ameliorating non-point source pollution, and sediment control as well as with providing vital habitat functions for terrestrial and aquatic species.Project Description
The Utah State Code requires the waters of the state of Utah be classified to protect against controllable pollution. Classification (e.g., protected for domestic use, swimming, game fish, and irrigation), coupled with priority listing by Utah's Non-Point Source Task force, has led to the establishment of a list of candidate watersheds that have experienced a variety of human induced disturbances leading to water quality impairment.We have identified four watersheds for study during the first phase of this project. The specific watersheds are the Little Bear River, Beaver River, Otter Creek, and Chalk Creek. These watersheds range in size between 500 and 2,000 km2 and they are geographically distributed across the state of Utah to represent the broad diversity of climate, hydrology, topography, and vegetation. Each of the watersheds represents a fourth- or fifth-order stream network with multiple second- or third-order tributaries linearly linked by unidirectional flow of water (energy), nutrients, and sediment. We propose to adopt these fifth-order watersheds as our upper limit for system study. Within these fifth-order watersheds, we plan to study in detail two or three second- or third-order tributaries, different by scale but intimately linked by flow. These tributary basins will range between 5 and 25 km2. We will use these sub-watersheds for our initial protocol development. Vegetation in these sub-watersheds predominately is characterized by shrub/steppe communities; the most common community is sagebrush/bunchgrass, followed by pinyon/juniper, then mountain brush and some aspen at higher elevations.
Our general approach will consist of three steps. First, we will identify sub-watersheds from within these four larger watersheds. Using historical data we will select those sub-watersheds that have known disturbances such as poor and good grazing practices, high number of roads and agricultural practices (includes range improvements e.g. fire, or mechanical). Second, we will use geographic information system models to identify surface and subsurface flow paths that determine riparian and upland monitoring sites upslope (up flow paths) of stream monitoring sites (Figure 1). Upland and riparian monitoring locations will be randomly located sites that fall along these flow pathways leading to stream monitoring sites (Figure 2). Finally, we will evaluate the utility of flow path models to characterize the linkages between upland, riparian, and stream monitoring locations.
Our sampling units will be the sub-watersheds. The sub-components of the watershed (upland, riparian and stream) will be the sub-samples that will provide an overall assessment of the watershed. The linkages developed by the modeling will allow managers to determine where problems exist in a watershed and allow management then to focus on problem areas. The vegetation data also will be used to assess the ecological condition of the upland and riparian areas.
