Irrigation district sustainability

Presented at Irrigation district sustainability - strategies to meet the challenges: USCID irrigation district specialty conference held on June 3-6, 2009 in Reno, Nevada.The Yolo County Flood Control & Water Conservation District (District) releases about 250,000 acre-feet per year from two water supply reservoirs in the Cache Creek watershed for the irrigation of about 60,000 acres of farmland in Yolo County, California. That water is diverted into the Winters Canal and the West Adams Canal at Capay Diversion Dam on Cache Creek. The continued operation of Capay Dam is vital to the sustained future of irrigated agriculture of the District. Urbanization and infrastructure construction in California resulted in extensive sand and gravel extraction from Cache Creek downstream of Capay Dam. Although that mineral extraction ceased many years ago, the streambed of Cache Creek has degraded. Presently the streambed elevation at the toe of Capay Dam is as much as 15 feet below the elevation of the apron of the dam and the dam is at risk due to downstream channel bed degradation and local scour during floods. Capay Dam is a concrete diversion that was constructed in 1915. The main portion of the dam is an overflow section about 475 feet long with low-level sluice gates and service spillways at both abutments. The abutments also contain the headworks for the irrigation canals. Due to streambed degradation, local scour at the toe of the apron and the more than 90-year service life of the structure, the District embarked on a program of dam inspection, including the use of non destructive testing of the concrete, and rehabilitating the dam and headworks so as to continue to provide a sustainable irrigation supply of surface water from Cache Creek. The dam inspection and rehabilitation and betterment program for Capay Diversion Dam is presented. This includes the issues of environmental permitting, stream morphology, sediment transport and historic data collection

Water-Resources Investigations Report 20-74

From introduction: The purpose of this report is to assemble empirical data on longitudinal dispersion for a variety of natural channels as a first step in the critical examination of current models used to describe longitudinal dispersion

The Energy Impact on Irrigated Agricultural Production of the Estancia Basin, New Mexico

A linear programming model was utilized to simulate a 20 year (1979-1998) crop production and irrigation water utilization pattern in the Estancia Basin of New Mexico under four alternative energy price projections--base, low, medium and high. Under the simulation approximately 31,300 acres of land would be farmed in 1978, rising to 46,300 acres in 1998 with 94 percent of the total being flood irrigated and the balance irrigated with sprin­klers. Alfalfa accounted for 40 percent of the irrigated cropland, corn for silage 25 percent, corn for grain 11 percent, wheat 10 percent, pinto beans 7 percent, and potatoes 5 percent. However, under the high energy price alternative, irrigated cropped agriculture would cease after 1996. Net returns to land and risk varied widely among the four energy price projections ranging from an increase of 158 percent in the base alternative from 1978 to 1998 to a 90 percent reduction in net returns in the high energy price alternative through 1996 and a 100 percent reduction by 1998. The reduction in net returns from 1978 to 1998 for the low energy price alternative was about 11 percent and about 58 percent for the medium energy price alternative. The reduction in net returns was due primarily to the rapid escalation of diesel fuel prices. The diesel fuel cost for the high alter­native was expected to increase 469 percent, 375 percent for the medium alternative, and about 220 percent for the low alternative over present costs. The returns to risk, after imposing a charge for the use of irrigated cropland valued at $1,000 per acre, was a negative$37 per acre in the base year of 1978. The negative returns to risk became even greater under the low ($60) and medium ($80) energy price alternatives in 1998, and high ($96) in 1996. Under the base price alternative, the net return to risk was estimated at a negative$33 per acre. The amount of irrigation water pumped in the Estancia Basin would increase 2.4 percent per year over the 20 year period for the energy price alternatives. The total declines in the water tables were estimated to be 26.5 feet (1.3 feet per year). In addition, there were changes in energy sources for pumping irrigation water, irrigation pumping plant efficiencies and energy costs for pumping irrigation water among the alternative energy price projections. The annual labor requirements and cost increased in relation to the increase in acreage, as did the annual operating capital requirements

The Energy Impact on Irrigated Agricultural Production of the Southwestern Closed Basins, New Mexico

A linear programming model was utilized to simulate a 20 year (1978-1998) crop production and irrigation water utilization pattern in the Southwestern Closed Basins of New Mexico under four alter­native energy price projections--base, low, medium and high. Under the simulation, approximately 75,700 acres of land would be farmed in 1978, remaining constant through 1998. Cotton accounted for 47 percent of the irrigated cropland, corn for grain 31 percent, grain sorghum 16 percent, and wheat 6 percent. However, under the high energy price alter­native, irrigated crop agriculture ceased in some areas in 1996 and in other areas in 1998. Net returns to land and risk varied widely among the four energy price projections ranging from an increase of one percent in the base alternative from 1978 to 1998 to a 62 percent reduction in net returns in the high energy price alternative through 1998. ·The reduction in net returns from 1978 to 1998 for the low energy price alternative was about 23 percent and about 40 percent for the medium energy price alternative. The reduction in net returns was due primarily to the rapid escalation of diesel fuel prices. The diesel fuel cost for the high alternative was expected to increase 269 per­cent, 185 percent for the medium alternative, and about 119 percent for the low alternative over present costs. The returns to risk, after imposing a charge for the use of irrigated cropland valued at $800 per acre, was$70 per acre in the base year of 1978. The returns to risk declined under the low ($49) and medium ($23) energy price alternatives in 1998. Under the high price alternative the net return to risk was estimated at a negative $10 per acre in 1998. The amount of irrigation water pumped in the Southwestern Closed Basins would remain constant over the 20 year period for the energy price alternatives, except 1996 and 1998 under the high alter­native when pumpage declined. The total declines in the water tables were estimated to be about 41 feet in the Mimbres-Uvas Basins, from 102 to 126 feet in the Columbus-Hermanas Area, about 34 feet in the Lordsburg-Animas Basins, and from 6 to 7 feet in the Playas Basin. In addition, there were changes in energy sources for pumping irrigation water, irrigation pumping plant efficiencies and energy costs for pumping irrigation water among the alternative energy prir.e projections. The annual labor requirements and cost as well as the annual operating capital requirements remained constant except under the high alternative when a decline occurred in relation to the decline in acreage

Oncogene-induced basement membrane invasiveness in human mammary epithelial cells

Expression of the intermediate filament protein vimentin, and loss of the cellular adhesion protein uvomorulin (E-cadherin) have been associated with increased invasiveness of established human breast cancer cell lines in vitro and in vivo. In the current study, we have further examined these relationships in oncogenically transformed human mammary epithelial cells. A normal human mammary epithelial strain, termed 184, was previously immortalized with benzo[a]pyrene, and two distinct sublines were derived (A1N4 and 184B5). These sublines were infected with retroviral vectors containing a single or two oncogenes of the nuclear, cytoplasmic, and plasma membrane-associated type (v-rasH, v-rasKi, v -mos, SV40T and c -myc). All infectants have been previously shown to exhibit some aspects of phenotypic transformation. In the current study, cellular invasiveness was determined in vitro using Matrigel, a reconstituted basement membrane extract. Lineage-specific differences were observed with respect to low constitutive invasiveness and invasive changes after infection with ras, despite similar ras-induced transformation of each line. Major effects on cellular invasiveness were observed after infection of the cells with two different oncogenes (v-rasH + SV40T and v -rasH + v -mos). In contrast, the effects of single oncogenes were only modest or negligible. All oncogenic infectants demonstrated increased attachment to laminin, but altered secretion of the 72 kDa and 92 kDa gelatinases was not associated with any aspect of malignant progression. Each of the two highly invasive double oncogene transformants were vimentinpositive and uvomorulin-negative, a phenotype indicative of the epithelial-mesenchymal transition (EMT) previously associated with invasiveness of established human breast cancer cell lines. Weakly invasive untransformed mammary epithelial cells in this study were positive for both vimentin and uvomorulin, suggesting that uvomorulin may over-ride the otherwise vimentin-associated invasiveness