Journal Articles

Computerized ground-water modeling has leapt from the cloistered laboratory to the field project as more and more programs are written for the personal computer. These easy-to-understand models can bridge the gap between the intuitive understanding of the scientist and the real-world need of the engineer and regulator. Scientists at Remcor recently simulated the hydrogeology beneath a Superfund site (the Springfield landfill near Springfield, Vt.) with a PC-based model. After reviewing the three dimensional results, the project engineers realized they could downsize their proposed treatment system and still remediate the site effectively. The engineers had suggested that ground water be extracted from the sand and gravel lens and treated with an on-site system that would consist of three wells able to pump 40-60 gpm. Based on the information from monitoring well installation and testing, a detailed three-layer model of the glacial till, an outwash sand and gravel lens, and bedrock was calibrated. The model was developed through MODFLOW from the U.S. Geological Survey. An appropriately constructed model is an important tool in helping someone understand natural processes and systems.

Water Resources Research Center Issue Paper No. 22.

The rapid growth in Arizona’s population, coupled with prolonged drought, has strained its already scarce water resources. Accommodating population growth in a responsible manner has required Arizona to be a leader and innovator in water policy. The Assured Water Supply Program requires 100 years of continuously, physically and legally available water for the areas where groundwater management is required. The Arizona Water Banking Authority, operating since 1997, has stored over three million acre-feet of Colorado River water in anticipation of future shortages. The Central Arizona Groundwater Replenishment District (CAGRD), authorized in 1993, enables affordable use of renewable water supplies by those without long-term contracts for Central Arizona Project (CAP) water and/ or the ability to deliver CAP water to their service areas. Arizona’s recharge and recovery statutes and regulations are central to all of these programs as well as the reuse of treated wastewater. Agriculture and municipal and industrial water users partner in a special recharge program, called the groundwater savings program. This program has conserved significant quantities of groundwater for future use.

Arizona's Groundwater Management Act limits the use of groundwater to meet growing demand for water by the municipal sector.  The state's recharge and recovery program allows for water reuse through aquifer recharge and later recovery inside or out of the area of hydrologic impact.  The paper discusses water reuse within the municipal sector in Arizona, with a special focus on the Tucson metropolitan area.  Increased effluent utilization is playing a more prominent role in long-range planning efforts.  The paper focuses on the role of reclaimed water in water management planning.  It explains how the use of effluent is influenced by water quality considerations and institutional/legal arrangements.

With a projected 25% and 50% increase in U.S. and world population, respectively, by the year 2050, substantial increases in freshwater use for food, fiber, and fuel production, as well as municipal and residential consumption, are inevitable. This increased water use will not come without consequences.

It is important to the economic vitality of the United States—including agriculture—that policymakers, water managers, and water users work collaboratively to achieve sustainable water resource management. Multiple issues require attention—water quality, environmental water needs, municipal demands for water, water resource availability, agricultural water use—and no issue can be addressed individually. This paper discusses the diverse demands for water resources—past, current, and future—using the impacts, regulations, challenges, and policies of specific U.S. states as examples. The authors indicate that the reliability of water quantity and quality deserves the attention of all levels of government and that private and public sector leadership will be critical.