Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Civil and Environmental Engineering


Richard C. Peralta


David Tarboton

Third Advisor:

Ryan Dupont


Water is crucial for domestic, agricultural, industrial, environmental, and hydropower uses. Once precipitation occurs, it eventually partitions into streamflow, evapotranspiration (ET), and groundwater recharge. Distribution of precipitation into these partitions is called a hydrologic budget. The hydrologic budget of any geographic area or watershed under different climate change conditions help water managers to make appropriate water management plans. Computer based hydrologic modeling software has been used extensively to solve many water resources problems including hydrologic budgets. Hydrologic modeling requires high quality weather parameter data.

This study projected surface and groundwater flows from the portion of RBC watershed that lies above Red Butte Reservoir (RBR) to Salt Lake Valley (SLV) for water years (WYs) 2051-2060 in two climatic Representative Concentration Pathways (RCPs) scenarios, RCP 4.5 and RCP 8.5. RCP 8.5 corresponds to the pathways with higher greenhouse gas emission than RCP 4.5. To project flows, we first used Hydrologic Engineering Center-Hydrologic Modeling System (HEC-HMS) 4.3 model to calibrate and validate the observed streamflow for WYs 2016 and 2017 respectively. However, within RBC study area weather stations, all three weather parameters (Precipitation (P), Temperature (T), and Net Radiation (NR)) required for HEC-HMS model were missing on the same day for some periods of WYs 2016-2017. This necessitated to fill the missing parameters prior to the model calibration and validation.

We hypothesized that systematically using ANN and SMs would enable making accurate estimates, even when multiple parameter values are missing on the same day. The hypothesis-estimated the missing weather parameters (P, T, and NR) values are useful for hydrologic modeling in a watershed. We ran the HEC-HMS validated model for WY 2051-2060 once for each RCP scenario, and quantified the flows to SLV. The model results showed that average stream and groundwater flows of WYs 2016 and 2017 were 14.1% and 55.7% of total study area precipitation, respectively. In the future 2051- 2060, compared with average annual surface and groundwater flows of WYs 2016-2017, percent changes in flows, respectively, were i) decreases of 29.6% and 24.2% for RCP 4.5 and ii) decreases of 26% and 23.9 % for RCP 8.5.



Available for download on Wednesday, May 01, 2024