Determining efficient project sites
Improvements save estimated 49,000 acre-feet of water yearly
By Jenna Smith
For more information regarding this subject, contact:
Allen Sturdivant
(956) 968-5581
awsturdivant@agprg.tamu.edu
With water shortage issues still the major concern in the Lower Rio Grande Valley (LRGV), economists and irrigation engineers have been hard at work evaluating infrastructure renovations.
With more than fifteen project sites analyzed to date, results pinpoint the most cost-efficient sites for continued improvements. By targeting these project areas, irrigation district managers in the Valley can save water at the lowest costs possible.
Allen Sturdivant, extension associate at the Texas A&M Agricultural Research and Extension Center in Weslaco, and a team of Texas A&M University economists continue to work with irrigation managers and their consulting engineers to determine the costs of saving both water and energy associated with rehabilitation projects.
"We hope to improve aged water-delivery systems servicing municipal, industrial and agriculture users along the Rio Grande," he said. "By efficiently improving irrigation infrastructure, users minimize costs to achieve water gains."
Sturdivant and his team use RGIDECON, a spreadsheet model with data input and calculations based on economic and financial principles which are consistent with capital budgeting. RGIDECON can analyze up to five components at the same time within a given project.
Among the fifteen new project sites analyzed in the Lower Rio Grande Valley, the Edinburg pipe project shows a $16 cost per acre-feet of water saved, a relatively low cost investment for saving water. On the more costly side, pumping plant improvements at the San Benito I Irrigation District cost $119 per acre-feet of water saved.
By comparing costs associated with different infrastructure improvements at various project sites, irrigation district managers can direct their time and money to improving those areas with lower costs. Other irrigation districts that have been analyzed in the most recent study include Harlingen, San Juan, Brownsville and San Benito II.
"Although the costs of saving water vary across projects, many are more economically attractive than other water saving procedures," he said. "The projects have been estimated to save a combined total of 49,000 acre-feet of water each year."
RGIDECON reports combined costs within a project, incorporating as many as six different measures into the final cost analysis. Measures may include initial construction costs, operating cost changes, current and historical water and energy savings, and expected useful life.
Three additional criteria measures such as water saved per dollar of cost, energy saved per dollar of cost and annual water savings per initial costs are also calculated for each project.
Sturdivant said that irrigation district managers, policymakers and agency representatives are using the results of the analyses to rebuild irrigation infrastructure within the region and save water at the lowest cost.
Renovations are targeted at the more cost efficient project sites, such as the pipelines of the Edinburg and Brownsville irrigation districts, which average a $21 and $28 per acre-feet of water cost.
"The Lower Rio Grande Valley must continue to address the present and future water supply imbalance," he said. "Therefore, efforts to identify and financially support the most cost-effective projects should be a priority for all stakeholders."
Though originally built for projects in the Rio Grande Valley, RGIDECON has a flexible design that can be used to analyze the capital investment alternatives of saving water and energy in other regions.
