Stochastic modeling of the rainfall-runoff process for nonpoint source pollutant load estimation

Thesis/Dissertation · Sun Jan 01 04:00:00 EST 1989

OSTI ID:5546608

Dickey, R O

A stochastic simulation methodology was developed for the rainfall runoff process to assist in the assessment of nonpoint source pollutant loads, particularly for ungaged watersheds where there is a scarcity or complete lack of historical data. The methodology was developed based on simulating individual rainfall-runoff events. A simulation model employed a rainfall simulator to stochastically generate rainfall event characteristics for input into basin hydrologic transformation functions which then predicted the corresponding runoff hydrograph characteristics. Also addressed was the impact of limited data availability on the ability to model the rainfall-runoff process. An evaluation was conducted of the degree to which committing valuable resources to expand the data base would provide measurable improvement in model results. Specifically, the probability of achieving certain levels of accuracy with the simulation model was statistically assessed as a function of the number of observed rainfall-runoff events used for model development. The probability of monitoring various numbers of rainfall-runoff events in specified time intervals was also established as an aid for planning field monitoring studies. The simulation methodology was applied to a study watershed in the Lake Ray Hubbard reservoir drainage basin near Dallas, Texas. Regional rainfall characteristics were established using historical hourly data from the Federal Aviation Administration rain gage at Love Field Airport in Dallas, Texas. Hourly rainfall data were resolved into individual rainfall events and probability density functions were identified for event volume, time between events, and event duration.

• Research Organization: Southern Methodist Univ., Dallas, TX (United States)
• OSTI ID: 5546608
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540120 -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
540320* -- Environment
Aquatic-- Chemicals Monitoring & Transport-- (1990-)
ATMOSPHERIC PRECIPITATIONS
DEVELOPED COUNTRIES
ENVIRONMENTAL TRANSPORT
FEDERAL REGION VI
HOURLY VARIATIONS
HYDROLOGY
MASS TRANSFER
MATHEMATICAL MODELS
NORTH AMERICA
POLLUTION
POLLUTION SOURCES
RAIN
RUNOFF
SIMULATION
SURFACE WATERS
TEXAS
USA
VARIATIONS
WATER POLLUTION
WATER RESERVOIRS
WATERSHEDS