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HEC-HMS Models for the Sacramento and San Joaquin River Basins Comprehensive Study

U.S. Army Corps of Engineers (USACE) | August 1st, 2001

Summary

Due to several large and damaging flood events on the Sacramento and San Joaquin Rivers (California) during the 1980s and 1990s, the U.S. House of Representatives

Due to several large and damaging flood events on the Sacramento and San Joaquin Rivers (California) during the 1980s and 1990s, the U.S. House of Representatives directed the Sacramento District to develop comprehensive plans for flood control for the two rivers and to develop hydrologic and hydraulic models of the river systems. The models will be used to provide better forecasts and evaluations of flood damage reduction alternatives. Additionally, the model results will be used as input for reservoir simulation models. The Sacramento River Basin and the San Joaquin River/Tulare Lake Bed Basins comprise nearly 60,000 square miles, drain California’s Central Valley floor and receive much of their runoff from the Sierra Nevada mountain range. Developing hydrologic models for the tributary basins (which included extremely variable terrain) within a ten month time period was a formidable task. The District contacted the Hydrologic Engineering Center (HEC) to assist with the development of these models. HEC used the Hydrologic Modeling System program, HEC-HMS, and introduced the HEC-GeoHMS grid-based technology to perform the hydrologic study. GeoHMS is an ArcView® extension that provides automated subbasin delineation methods and calculates many physical characteristics used for estimation of hydrologic parameters. HEC developed and calibrated 33 individual HEC-HMS models for the major tributaries and portions of the valley floors of the Sacramento River Basin and the San Joaquin River / Tulare Lake Bed Basins. GeoHMS was used to delineate the individual river basins, perform initial subbasin delineation and develop the physical characteristics for the subbasins. Tools within GeoHMS allowed the modelers to iteratively redelineate their subbasins, as appropriate, to meet project needs. Keeping the modeling effort consistent was critical to the success of the study. To ensure this consistency of procedures and results, HEC developed modeling guidelines that each of the 11 modeling teams followed. Once the grid-based HEC-HMS models were developed, HEC contracted with the Corps’ Cold Regions Research and Engineering Laboratory (CRREL) to perform a snowmelt study for the watersheds. HEC provided a gridded precipitation file (4 km2) to CRREL. Through the use of their Distributed Snow Process Model (DSPM), CRREL then provided a gridded snowmelt/ precipitation file to HEC. DSPM computes snowmelt and rainfall depths at the soil surface on a grid-cell basis. This data is used directly by HEC-HMS as precipitation on the watershed. The ModClark rainfall to runoff transformation was used to compute the subbasin hydrographs. HEC-HMS parameter optimization models were developed at hourly flow gages for the unregulated headwater streams. The runoff parameter optimization models allowed the modelers to develop the runoff parameters necessary for the regression analysis. A number of physical characteristics were evaluated for correlation with variations in Clark’s time of concentration, TC, for the optimization models. The results of the regression analysis allowed the modelers to populate the ungaged subbasins with appropriate unit hydrograph parameters. Approximately 200 hourly flow gages and 83 reservoirs were considered in calibrating the models. The 33 individual basin models were then given to the Sacramento District.

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Historical and future relations between large storms and droughts in California

University of California, Davis (UC Davis) | July 14th, 2016

Summary

California precipitation varies more dramatically from year to year than elsewhere in the conterminous United States. This paper analyzes the extent to which contribution

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Human influence on joint changes in temperature, rainfall and continental aridity

Nature Portfolio (Springer Nature) | July 6th, 2020

Summary

Despite the pervasive impact of drought on human and natural systems, the large-scale mechanisms conducive to regional drying remain poorly understood. Here we us

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Human-induced changes in wind, temperature and relative humidity during Santa Ana events

Climatic Change (Springer) | November 24th, 2011

Summary

The frequency and character of Southern California’s Santa Ana wind events are investigated within a 12-km-resolution downscaling of late-20th and mid-21st century time

The frequency and character of Southern California’s Santa Ana wind events are investigated within a 12-km-resolution downscaling of late-20th and mid-21st century time periods of the National Center for Atmospheric Research Community Climate System Model global climate change scenario run. The number of Santa Ana days per winter season is approximately 20% fewer in the mid 21st century compared to the late 20th century. Since the only systematic and sustained difference between these two periods is the level of anthropogenic forcing, this effect is anthropogenic in origin. In both time periods, Santa Ana winds are partly katabatically-driven by a temperature difference between the cold wintertime air pooling in the desert against coastal mountains and the adjacent warm air over the ocean. However, this katabatic mechanism is significantly weaker during the mid 21st century time period. This occurs because of the well-documented differential warming associated with transient climate change, with more warming in the desert interior than over the ocean. Thus the mechanism responsible for the decrease in Santa Ana frequency originates from a well-known aspect of the climate response to increasing greenhouse gases, but cannot be understood or simulated without mesoscale atmospheric dynamics. In addition to the change in Santa Ana frequency, we investigate changes during Santa Anas in two other meteorological variables known to be relevant to fire weather conditions—relative humidity and temperature. We find a decrease in the relative humidity and an increase in temperature. Both these changes would favor fire. A fire behavior model accounting for changes in wind, temperature, and relative humidity simultaneously is necessary to draw firm conclusions about future fire risk and growth associated with Santa Ana events. While our results are somewhat limited by a relatively small sample size, they illustrate an observed and explainable regional change in climate due to plausible mesoscale processes.

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Hydraulic and mechanical properties affecting ground‐water flow and aquifer‐system compaction, San Joaquin Valley, California

U.S. Geological Survey (USGS) | July 19th, 2001

Summary

This report summarizes hydraulic and mechanical properties affecting ground-water flow and aquifer-system compaction in the San Joaquin Valley, a broad alluviated inte

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Hydraulic fracturing in faulted sedimentary basins: Numerical simulation of potential contamination of shallow aquifers over long time scales

American Geophysical Union (AGU) | December 12th, 2013

Summary

Hydraulic fracturing, used to economically produce natural gas from shale formations, has raised environmental concerns. The objective of this study is to assess one of

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Hydraulic-Property Estimates for Use With a Transient Ground-Water Flow Model of the Death Valley Regional Ground-Water Flow System, Nevada and California

U.S. Geological Survey (USGS) | July 2nd, 2001

Summary

The Death Valley regional ground-water flow system encompasses an area of about 43,500 square kilometers in southeastern California and southern Nevada, between latitu

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Hydro-economic analysis of groundwater pumping for irrigated agriculture in California’s Central Valley, USA

Hydrogeology Journal (Springer) | July 12th, 2015

Summary

As in many places, groundwater in California (USA) is the major alternative water source for agriculture during drought, so groundwater’s availability will drive some i

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Hydro-economic models: Concepts, design, applications, and future prospects

Journal of Hydrology (Elsevier) | September 15th, 2009

Summary

Future water management will shift from building new water supply systems to better operating existing ones. The variation of water values in time and space will

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Hydrodynamic and Water Quality Model Calibration and Application in San Francisco Bay

San Francisco Estuary Institute (SFEI) | September 3rd, 2018

Summary

To answer management questions about nutrient related water quality in San Francisco Bay, hydrodynamic and biogeochemical models have been developed. This report outline

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Page : 26

HEC-HMS Models for the Sacramento and San Joaquin River Basins Comprehensive Study

Historical and future relations between large storms and droughts in California

Human influence on joint changes in temperature, rainfall and continental aridity

Human-induced changes in wind, temperature and relative humidity during Santa Ana events

Hydraulic and mechanical properties affecting ground‐water flow and aquifer‐system compaction, San Joaquin Valley, California

Hydraulic fracturing in faulted sedimentary basins: Numerical simulation of potential contamination of shallow aquifers over long time scales

Hydraulic-Property Estimates for Use With a Transient Ground-Water Flow Model of the Death Valley Regional Ground-Water Flow System, Nevada and California

Hydro-economic analysis of groundwater pumping for irrigated agriculture in California’s Central Valley, USA

Hydro-economic models: Concepts, design, applications, and future prospects

Hydrodynamic and Water Quality Model Calibration and Application in San Francisco Bay

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