Runoff Modeling of a Coastal Basin to Assess Variations in Response to Shifting Climate and Land Use: Implications for Managed Recharge
- 20 Downloads
We quantified the distribution of hillslope runoff under different climate and land-use conditions in a coastal, mixed land-use basin, the Pajaro Valley Drainage Basin (PVDB), California, USA, in order to evaluate opportunities to improve groundwater supply. We developed dry, normal, and wet climate scenarios using high-resolution historic data and compared contemporary land use to pre-development land use under the different climate scenarios. Relative to pre-development conditions, urban and agricultural development resulted in more than twice as much simulated runoff generation, greater spatial variability in runoff, and less water available for recharge; these differences were most pronounced during the dry climate scenario. Runoff results were considered in terms of potential to support distributed stormwater collection linked to managed aquifer recharge (DSC-MAR), which routes excess hillslope runoff to sites where it can infiltrate and enhance groundwater recharge. In the PVDB, 10% of the annual groundwater deficit could be addressed by recharging 4.3% of basin-wide hillslope runoff generated during the normal scenario, and 10.0% and 1.5% of runoff during the dry and wet scenarios, respectively. Runoff simulation results were combined with an independent recharge suitability mapping analysis, showing that DSC-MAR could be effective in many parts of the PVDB under a range of climate conditions. These results highlight the importance of strategically locating DSC-MAR projects at the confluence of reliable supply and favorable subsurface hydrologic properties.
KeywordsHillslope runoff Stormwater collection Managed aquifer recharge Groundwater management Land use development Climate and hydrology
This project was funded by the California Coastal Conservancy (13-118); the University of California Water Security and Sustainability Research Initiative (449214-RB-69085), supported by the UC Office of the President’s Multi-Campus Research Programs and Initiatives (MR-15-328473); a Graduate Research Fellowship from the US National Science Foundation; the Gordon and Betty Moore Foundation (GBMF5595); and The Recharge Initiative (http://www.rechargeinitiative.org/).
Compliance with Ethical Standards
Conflict of Interest
The authors declare that they have no conflict of interest.
- Cvijanovic I, Santer BD, Bonfils C et al (2017) Future loss of Arctic Sea-ice cover could drive a substantial decrease in California’s rainfall. Nat Commun 8. https://doi.org/10.1038/s41467-017-01907-4
- Fisher A, Lozano S, Beganskas S et al (2017) Regional managed aquifer recharge and runoff analyses in Santa Cruz and northern Monterey counties. California. https://doi.org/10.7291/V9Q81B7W
- Khaliq MN, Ouarda TBMJ, Gachon P et al (2009) Identification of hydrological trends in the presence of serial and cross correlations: a review of selected methods and their application to annual flow regimes of Canadian rivers. J Hydrol 368:117–130. https://doi.org/10.1016/j.jhydrol.2009.01.035 CrossRefGoogle Scholar
- Kiparsky M, Fisher AT, Hanemann WM, et al (2018) Issue brief: Recharge net metering to enhance groundwater sustainability. Center for Law, Energy, and the Environment, University of California at Berkeley, BerkeleyGoogle Scholar
- Liu SC, Fu C, Shiu C-J et al (2009) Temperature dependence of global precipitation extremes. Geophys Res Lett 36. https://doi.org/10.1029/2009GL040218
- Markstrom SL, Regan RS, Hay LE, et al (2015) PRMS-IV, Precipitation-Runoff Modeling System. U.S. Geological SurveyGoogle Scholar
- Page D, Vanderzalm J, Dillon P et al (2016) Stormwater quality review to evaluate treatment for drinking water supply via managed aquifer recharge. Water Air Soil Pollut 227. https://doi.org/10.1007/s11270-016-3021-x
- PVWMA (2014) Basin Management Plan Update, Final: February 2014. Pajaro Valley Water Management Agency, WatsonvilleGoogle Scholar
- Santa Cruz County (2016) Santa Cruz County 2016 Crop ReportGoogle Scholar
- Swain DL, Langenbrunner B, Neelin JD, Hall A (2018) Increasing precipitation volatility in twenty-first-century California. Nat Clim Chang. https://doi.org/10.1038/s41558-018-0140-y