Description |
Farmington Bay is an important natural resource for the state of Utah, providing wetland habitats including freshwater and salt water, marshes, mud flats, and upland areas. The primary water source for Farmington Bay is the Jordan River, which receives water from natural and urban runoff in the Salt Lake Valley. This thesis work is guided by broad interest in evaluating implications of green infrastructure as a stormwater management practice on return flows under current and potential future climate change scenarios. The ultimate goal was to create a model to explore the impacts that bioretention, rainwater harvesting, and climate change may have, individually and combined, on the downstream stakeholders and receiving water systems in the Salt Lake Valley. This was performed using integrated modeling techniques through use of GoldSim software. Overall, the model demonstrated that bioretention and rainwater harvesting individually and combined showed minimal to no impacts to downstream water users, Jordan River flows, and ultimately Farmington Bay water levels. Bioretention reduced the flow in the Jordan River by less than 1%, primarily during peak flow. Rainwater harvesting actually kept more water in the natural system on average because less water was needed from the water treatment facilities when outdoor irrigation was supplemented with rainwater. This means more water stayed in the upstream reservoir or bypassed to the Jordan River. The user reliability did not differ for any of the bioretention and rainwater harvesting scenarios. Climate change had the greatest impact to Jordan River flows, Farmington Bay water levels, and user reliability. The selected 20% reduction in tributary flows and precipitation led to an average decrease of 11% in the Jordan River streamflow when compared to average baseline scenario over a 25-year simulation. The user reliability decreased by 5% and most importantly, there was found to be an average of 36% decrease in the water levels in Farmington Bay, with a critical level of 41,000 acre-feet reached. The resultant of this is a loss of up to 15,000 acres of open bay that would impact bird habitat, brine shrimp grounds, recreationalists, bird watchers, hunters, and more. |