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Renewable Energy
Published in Efstathios E. Michaelides, Energy, the Environment, and Sustainability, 2018
The potential and kinetic energies of water has been used as a source of power with watermills for thousands of years. At present, much bigger power plants convert the energy of several rivers to electricity. A river with relatively high mass flow rate is restricted by a dam, which is constructed at a location where a significant drop in the river elevation occurs, often in a region of waterfalls. The dam creates an artificial water reservoir upstream, which may store billions or trillions of cubic meters of water.1 The capacity of artificial water reservoirs is measured in acre feet of water, with 1 acre ft being equal to 326,000 gal or 1,239 m3 of water. In addition to electric power generation, dams and reservoirs regulate the seasonal water flow in the river and have become parts of large-scale irrigation projects.
The Science of Soil Mechanics
Published in Frank R. Spellman, Land Subsidence Mitigation, 2017
Not only is water a vital component of every living being, but it is also essential toplant growth and to the microorganisms that live in the soil, in addition to beingimportant in the weathering process, which involves the breakdown of rocks andminerals to form soil and release plant nutrients. In this section, we focus on soilwater and its importance in soil, but first we need to take a closer look at water—what it is and its physical properties. Water exists as a liquid between 0° and 100°C (32° to 212°F), as a solid at or below 0°C (32°F), and as a gas at or above 100°C(212°F). One gallon of water weighs 8.33 pounds (3.778 kilograms) and is equalto 3.785 liters. One cubic foot of water equals 7.5 gallons (28.35 liters). One ton ofwater equals 240 gallons. One acre-foot of water equals 43,560 cubic feet (325,900gallons). Earth’s rate of rainfall equals 340 cubic miles per day (16 million tons persecond). Finally, water is dynamic (constantly in motion). It evaporates from seas,lakes, and the soil; is transported through the atmosphere; falls to Earth; runs acrossthe land; and filters downward into and through the soil to flow along rock strata.
Cheaper Than Dirt
Published in Terry L. Anderson, Brandon Scarborough, Lawrence R. Watson, Tapping Water Markets, 2012
Terry L. Anderson, Brandon Scarborough, Lawrence R. Watson
Well-defined, enforced, and tradable property rights are key to getting owners to take account of opportunity costs. Consider each of these three elements in the context of water rights. Defining water rights requires some unit of measurement. In the early mining camps, rights were specified in “miner’s inches,” the amount of water that would flow through a one-square inch hole cut in a board inserted in the channel. Today it is more common to measure flows in gallons or cubic meters per second and volumes in acre-feet—the amount of water necessary to cover one acre of land one foot deep with water. Well-defined water rights must specify the quantity of water that can be diverted from a stream, the timing of the diversion, and the quantity and quality that must be returned. When not all claims on a stream can be met, water rights must specify whose rights, if any, have priority or whether all must reduce diversions proportionately.
Carrot or stick: what motivates urban water consumption? Evidence from Southern California
Published in International Journal of Water Resources Development, 2023
The compiled data from MWD (various years) annual reports comprise annual water consumption of its 26 member agencies over 12 years (see Table A1 in the supplemental data online, with approximate service area and population). The panel data are used to examine the overall reduction in consumption in the MWD service region during the water-use restriction period with respect to the consumption in years witnessing drought, normal precipitation (post-drought) and voluntary conservation policies. Table 2 provides the summary statistics for the 312 yearly water consumption data and its key variables. The unit of analysis is the total water produced or used per water agency per year. The outcome variable is the total annual water consumption or use (presented in thousand acre-feet; 1 acre-foot = 1.23 million litres) per water supplier. This includes local water use as well as water received from MWD sources for consumptive purposes. It does not include surplus water sold to adjacent regions or put in underground storages. The mean or average volume of water consumed per member agency is found to be 138 thousand acre-feet per year.
Large-scale water development in the United States: TVA and the California State Water Project
Published in International Journal of Water Resources Development, 2023
In its current configuration, the SWP serves a population of nearly 27 million and some 750,000 acres of farmland. This utilizes 36 storage facilities, including Orville Dam, pumping and pumping–generating plants, hydroelectric plants, and some 700 miles of canals, tunnels and pipelines. The major transmission facility is the California Aqueduct, a concrete canal that extends from the Delta through the Central Valley and on to the Edmonston Pumping Plant, which is the highest single-lift pumping plant in the world and lifts water over the Tehachapi Mountains. The aqueduct has several branches, and the main portion is 444 miles long. Operationally, the project was built to deliver about 4.2 million acre-feet per year to 29 public agency contractors. In the recent decade, it has averaged 2.8 million acre-feet in deliveries (California Water Department of Water Resources (DWR), 2020a; Water Education Foundation, 2020a).
Hypolimnetic oxygenation 6. Improvement in fisheries, hydropower, and drought management with costs of installation and operation in Camanche Reservoir, California, United States
Published in Lake and Reservoir Management, 2022
Alex J. Horne, William K. Faisst
The higher minimum water level suggested for Camanche River was 24.2 m vs. 21.2 m—a volume of 57 million m3 (∼46,000 acre-feet, af), 11% of the full reservoir and 16% of its typical summer volume. The delay in onset of deepwater anoxia due to a 3 m increase in water level in Camanche Reservoir given the hypolimnetic water DO decline of ∼0.1 mg/L/day was calculated as only a few days. Fish kills would still have occurred, and the additional water would have provided no reduction in H2S production, nutrients, algae, ammonia, heavy metals, and turbidity. With HOS, Camanche Reservoir can now operate at a lower level in droughts and still provide good quality hypolimnetic releases. Nonetheless, levels cannot be allowed to decrease too much since destratification will occur. This was a contributing factor for the 1987 fish kills, and a minimum volume for cool water in the hypolimnion was adopted as an operational rule along with HOS in 1993 (Horne 2019a). Therefore, HOS with a minimum hypolimnion pool was more cost-efficient than the higher water level alone alternative.