Analysis Of The Efficacy Of The Kino Environmental Restoration Project: A Comparison Between Flow Data And Formula Predictions
Presenter: Josh Arden1
Co-Author(s): Eleonora Demaria
Advisor(s): Dr. Martha Whitaker
1Department of Geosciences, The University of Arizona
Panapto Presentation Video
Poster PDF
Poster Session 1
The Kino Environmental Restoration Project (KERP) is a detention-retention facility that helps with flood control and collects stormwater for use in its nature-mimicking landscape as well as irrigation. Pima County Regional Flood Control District (PCRFCD) made estimations of total runoff to design KERP based on regression equations between the area of the contributing watershed and the percentage of impervious area and their efficacy, which has not been assessed. Since the year 2003, PCRFCD has been measuring surface runoff entering KERP. To determine the accuracy of the empirical equations used to design KERP, I constructed hydrographs for all flow events from 2003 to 2021 based on data provided by a stream gauge located at the KERP inflow site. Approximate values were calculated by integration of the hydrographs using the trapezoid method to approximate total volumes, for individual storms and total annual volumes. Delineation of the KERP watershed boundary was accomplished using ArcGIS. Yearly flows varied substantially, ranging from 19 acre-feet in 2020 to 7,410 acre-feet in 2007; this range is significantly higher than predicted by the empirical equations. Fortunately, KERP was intentionally overbuilt to account for larger accumulated runoff volumes; in other words, KERP’s “overcapacity” based on initial predictions have proven to be beneficial by providing a surplus of usable stormwater. KERP volumes should continue to be monitored, since a longer study time may produce a statistically significant difference in results, especially with the likelihood of larger-intensity storms due to climate change.