Water Resources Research Act Program

Details for Project ID 2020MD191B

Precipitation frequency in Maryland: Investigating epistemic uncertainty

Institute: Maryland
Year Established: 2020 Start Date: 2020-03-01 End Date: 2021-02-28
Total Federal Funds: $17,278 Total Non-Federal Funds: $34,951

Principal Investigators: Michelle T Bensi

Abstract: Maryland engineering practices for design of storm water management systems select rainfall quantities used for sizing of storage and conveyance systems based on the frequency (probability) of exceedance associated with a specific rainfall quantity and duration. This precipitation-frequency information is coupled with idealized temporal distributions for how rainfall will be distributed over a storm of a specific duration. The frequency and design-storm information currently available does not generally quantify the effects of uncertainties arising from different technical interpretations of data, models, and methods used in performing an analysis, known as epistemic uncertainty. Potentially important sources of epistemic uncertainties include the choice of probability distribution, parameter estimation method, and data series specification. The proposed work seeks to understand the magnitude and implications of these epistemic uncertainties for frequency estimates and design storms under current and future climate in Maryland.