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Precipitation Depth-Duration and Frequency Characteristics for Antelope Valley, Mojave Desert, California

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Precipitation Depth-Duration and Frequency Characteristics for Antelope Valley, Mojave Desert, California PRECIPITATION DEPTH-DURATION AND FREQUENCY CHARACTERISTICS FOR ANTELOPE VALLEY, MOJAVE DESERT, CALIFORNIA U.S. GEOLOGICAL SURVEY Water-Resources Investigations Report 95-4O56 Prepared in cooperation with LOS ANGELES COUNTY, CALIFORNIA Three-dimensional sketch of average historical storm depths throughout Antelope Valley. View from northeast to southwest. CONTENTS Abstract.................................................................................................................................................................................. 1 Introduction ....................................................................................................................._^ 1 Description of Study Area........................................................................................................................................... 3 Purpose and Scope....................................................................................................................................................... 6 Data Collection.............................................................................................................................................................^ 6 Seasonal Variation in Precipitation........................................................................................................................................ 10 Precipitation Depth-Duration Characteristics........................................................................................................................ 10 Disaggregation of Daily Total Precipitation Data....................................................................................................... 11 Disaggregation of Hourly Total Precipitation Data..................................................................................................... 15 Regional Characteristics of Selected Storms......................................................................................................................... 21 Maximum 24-Hour Total Precipitation and Frequency......................................................................................................... 25 Summary.........................................................................................................................»^ 32 References ......................................................................................................................._^ 33 FIGURES 1. Map showing location of Antelope Valley, California, and stream-gaging stations.............................................. 2 2. Graph showing annual total and maximum 24-hour precipitation depths at Palmdale, California, 1933-93........ 3 3. Map showing locations of precipitation stations in Antelope Valley, California, and vicinity.............................. 7 4. Graph showing annual peak discharges of Big Rock Creek near Valyermo, California, 1923-93 ........................ 8 5. Photograph of precipitation stations at Rogers Lake Tributary, Edwards Air Force Base, California................... 9 6. Graph showing seasonal distribution of storms at selected stations in Antelope Valley, California, 1918-92...... 11 7. Map showing mean annual precipitation in Antelope Valley, California............................................................... 12 8-12. Graphs showing: 8. Average precipitation depth-duration relations for 12 storms at selected stations in Antelope Valley, California.................................................................................................................... 14 9. Fifteen-minute total precipitation and discharge for the storm of March 26-27,1991, at two stations in Antelope Valley, California, Rogers Lake Tributary at Edwards Air Force Base and Somerset Creek at Palmdale................................................................................................................... 16 10. Depth-duration ratios for maximum recorded hourly precipitation depths in Antelope Valley, Califoniia..................................................^ 17 11. Depth-duration relations for maximum recorded precipitation depths for intervals of less than 60 minutes, Antelope Valley, California................................................................................................. 20 12. Maximum observed depth-duration ratios for intervals of less than 60 minutes, Antelope Valley, California.................................................^ 20 13. Map showing areal variation of maximum 24-hour precipitation depths for 23 selected storms, Antelope Valley, California, and vicinity, 1938-93...................................................................................... 24 14. Graphs showing recurrence intervals of annual maximum 24-hour precipitation depths at selected stations in Antelope Valley, California......................................................................................................... 26 Contents III TABLES 1. Precipitation stations in Antelope Valley, California, and vicinity......................................................................... 4 2. Catchment for various types of rain gages at U.S. Geological Survey stream-gaging and precipitation stations in Antelope Valley, California.............................................................................................................. 9 3. Maximum precipitation depths for durations of 24 hours or less for selected storms and stations in Antelope Valley, California............................................................................................................................... 13 4. Maximum precipitation depths for storm of January 5, 1992, at selected time intervals for the Somerset Creek station, California.................................................................................................................... 15 5. Precipitation intensity for selected stations and storms in Antelope Valley, California, and vicinity, 1943-93..... 18 6. Maximum precipitation depths for selected intervals and 24-hour totals at U.S. Geological Survey precipitation stations, Antelope Valley, California, 1990-93............................................................................. 18 7. Total measured and estimated precipitation for selected durations for the storm of February 9-12,1992, at Palmdale, California, and vicinity..................................................................................................................... 21 8. Maximum 24-hour precipitation depths for selected storms, 1938-93, in Antelope Valley, California................. 22 9. Precipitation stations used in estimating generalized skew of annual maximum 24-hour precipitation depths in Antelope Valley, California................................................................................................................ 30 10. Precipitation depth-duration and frequencies at selected stations for selected storms in Antelope Valley, California............................................................................................................................... 31 CONVERSION FACTORS Multiply By To obtain acre 0.4047 hectare cubic foot per second (ft3/s) 0.02832 cubic meter per second foot (ft) 0.3048 meter inch (in.) 25.40 millimeter inch per year (in/yr) 25.40 millimeter per year miles (mi) 1.609 kilometers square mile (mi2) 259.0 square kilometers Sea level: In this report, "sea level" refers to the National Geodetic Vertical Datum of 1929 (NGVD of 1929) a geodetic datum derived from a general adjustment of the first- order level nets of both the United States and Canada, formerly called Sea Level Datum of 1929. All elevations given in this report are referenced to sea level. Abbreviations EAFB Department of the Air Force, Edwards Air Force Base, California LACDPW Los Angeles County Department of Public Works LACFCD Los Angeles County Flood Control District NOAA National Oceanic and Atmospheric Administration USGS United States Geological Survey IV Contents Precipitation Depth-Duration and Frequency Characteristics for Antelope Valley, Mojave Desert, California By James C. Blodgett Abstract with precipitation depths that equal or exceed 0.60 inch per hour. The storms of January 1943 Methods to evaluate changes in the volume and March 1983 were the most intense storms of of storm runoff from drainage basins that are record, with recurrence intervals greater than 100 likely to be urbanized are needed by land-use years in some parts of the valley. planning agencies to establish criteria for the Depth-duration ratios were calculated by design of flood-control systems. To document the disaggregating daily total precipitation data for changes in runoff volume of basins that may be intervals of 1, 2, 3,4, 6, 12, and 18 hours for urbanized, nine small basins that are considered storms that occurred during 1990-93. The hourly representative of varying hydrologic conditions in total precipitation data were then disaggregated at Antelope Valley, California, were selected for 5-minute intervals. A comparison of the depth- detailed study. Precipitation and stream-gaging duration data collected during 1990-93 at the stations were established and data were collected Geological Survey stations with the data collected for the period 1990-93. The data collected at at the other stations indicated that the 1990-93 these U.S. Geological Survey stations were sup­ data are not representative of historical storms. plemented by data collected at 35 long-term pre­ Therefore, depth-duration
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