Fallon NAS was constructed in the 1940s on land that previously had been farmed using water provided by the Bureau of Reclamation's Newlands Reclamation Project. Prior to the project, which was authorized in 1903, early settlers irrigated about 20,000 acres using simple diversions from the Truckee and Carson rivers. The Newlands project nearly quadrupled the amount of irrigated land to 78,000 acres, and the land surrounding the airfield has been irrigated farmland since. In the 1950s, the Navy obtained, as a buffer against encroachment, land surrounding the airfield that had been irrigated farmland. It has since leased the bulk of that land to farmers. Fallon NAS officials believe that continued use of the land for agriculture is of value to the local community as well as to the air station. They point out that the City of Fallon and Churchill County are concerned that any reduction in Fallon NAS' irrigation could have a negative impact on the recharging of the underlying aquifer, cause the manifestation of noxious weeds in fields, and have an impact on the economics of neighboring ranches and farms. The Navy currently holds water rights under the Newlands project for approximately 2,900 acres of the land at Fallon NAS. Of this acreage, the Navy has active water rights to about 1,900 acres of land. Water rights are attached to specific parcels of land, and Fallon NAS is entitled to 3.5 acre- feet of water per acre of water-righted land from the Newlands project. An acre-foot is the volume of water sufficient to cover an acre of land to the depth of 1 foot, which is about 325,900 gallons. The water rights for the remaining 1,000 acres are inactive. The active water rights, which would equal about 2.2 billion gallons, are used to obtain irrigation water to support the Navy's 3,595-acre greenbelt surrounding Fallon NAS' airstrip areas. The greenbelt has consumed an average of 1.6 billion gallons of this irrigation water each year since 1990. This figure includes drought years in which less water than the normal allocation was available and other years in which water over and above the acreage's entitlement was made available. As can be seen in figure 1, about a third of the greenbelt acreage lies inside the runway protection zone. Under Public Law 101-618, enacted in 1990, officials at Fallon NAS were required to develop an alternative land management plan that would control dust, provide for fire abatement and safety, and control damage to aircraft from foreign objects, while at the same time reducing the use of irrigation water. The law also required Fallon NAS to select and implement land management plans without impairing the safety of air operations. Under this act, the Navy has discretion to determine what constitutes operational air safety for Fallon NAS. In addition, the Secretary of the Navy was required to consult with the Secretary of Agriculture and other interested parties to fund and implement a demonstration project and test site at Fallon NAS for the cultivation and development of grasses, shrubs, and other native plant species. The project's goal was to help with the restoration of previously irrigated farmland in the Newlands project area to a stable and ecologically appropriate dryland condition. In responding to the act's requirements, the Navy studied various land management strategies, consulted with the Secretary of Agriculture and interested parties, and selected a strategy for the greenbelt that combines conventional farming with water conservation practices. Fallon NAS officials have started to implement this strategy for the runway protection zone. When fully implemented, the strategy would use approximately 1.4 billion gallons of water per year, somewhat of a decrease from the average of 1.6 billion gallons used annually in recent years. Fallon NAS is governed by aviation safety and operational standards established by DOD for runway protection zones. DOD's standards for military facilities and the Federal Aviation Administration's (FAA) standards for commercial airports require runway protection zones to protect lives and property. Under these standards, airports can obtain sufficient authority to restrict the use of the land for the runway protection zones in three primary ways. First, an airport can purchase the approach areas outright. Second, an airport can seek zoning requirements to control the way land owned by others is used. Third, an airport can purchase easements proscribing the incompatible use of land owned by others. Outright ownership is preferable because it gives an airport maximum control. It is DOD's and FAA's policy to oppose incompatible land uses that are proposed for property within the runway protection zones. Incompatible land uses include residences and places of public assembly such as churches, schools, hospitals, office buildings, and shopping centers. Compatible land uses within the runway protection zones are generally uses such as agriculture or golf courses that do not involve concentrations of people or the construction of buildings or other structures. DOD and FAA also allow other land uses that do not attract wildlife and that do not interfere with navigational aids. Neither policy requires the establishment of a greenbelt. In arriving at the land management strategy for Fallon NAS, the Navy considered three alternatives in detail. Each involved continued irrigation of land in Fallon NAS' greenbelt. As many as 11 different land management strategies were identified by Fallon NAS officials at the outset. Three strategies were eliminated from consideration before the initial screening was conducted. These three included covering the greenbelt with asphalt, cement, or rocks, or allowing the irrigated fields to go fallow. These strategies were eliminated because the officials believed that they would be environmentally or economically unacceptable or would cause unacceptable operational or safety impairments. They also felt that the strategies would be expensive to maintain and would not provide a “soft” landing for any aircraft accident. The remaining eight land management strategies were subjected to an initial screening on the basis of how they would contribute to the Navy's policy of zero accidental aircraft mishaps and at the same time fulfill the requirements of P.L. 101-618. Four evaluation criteria were used to assess the viability of the strategies: controlling dust and damage from foreign objects, including bird strikes; minimizing fire hazards; establishing a high probability of achieving safety objectives and contributing to zero-mishap management; and reducing the direct surface deliveries of irrigation water. Of the eight land management strategies, five were eliminated because Fallon NAS officials believed those strategies did not meet the evaluation criteria. These five strategies ranged from changing the plants allowed to be grown in the area to using drainwater for irrigation. The remaining three land use strategies were then subjected to detailed consideration. Table 1 presents a comparison of the features of the three strategies Fallon NAS officials considered in detail. The first and second strategies considered in detail included water conservation practices. The methods considered for saving water included lining canals, leveling fields for proper drainage, establishing windbreaks, and improving irrigation scheduling. The third strategy would not have required any changes to the way Fallon NAS officials had been managing the greenbelt land but would have reduced the use of water by irrigating fewer acres. Fallon NAS officials believed that, over time, this strategy would result in land degradation and that there was a low probability that it would control safety hazards such as dust, fire, and damage to aircraft from foreign objects and bird strikes. In considering these strategies, Fallon NAS officials made no distinction between the greenbelt areas that lie within the runway protection zone and the areas that lie outside the zone. Approximately 1,145 acres of the greenbelt lie within the runway protection zone, while 2,450 acres are outside of it. We found no analysis that had determined whether the 2,450 acres of the greenbelt outside the runway protection zone required the same level of prevention of foreign objects, bird strikes, or dust as the 1,145 acres within the zone. Fallon NAS officials confirmed that no such distinction had been made in conducting their analyses. Fallon NAS officials selected the first strategy: conventional farming with water conservation practices. At the time, these officials believed that the advantages of this strategy were the very high probability that it would satisfy the safety goals for the greenbelt for the long term and provide moderate water savings. They believed that the disadvantage would be the substantial capital, operations, and maintenance costs of the water conservation methods. When fully implemented, the chosen strategy would encompass 1,914 water-righted acres of land, using approximately 1.4 billion gallons of water per year. Navy officials believed that the plan would be costly to implement because it included lining irrigation canals with concrete, leveling fields for proper drainage, and other measures. According to Navy officials, the total cost to implement all these measures could be as much as $3.5 million. Since selecting the strategy of conventional farming with water conservation practices in 1995, Fallon NAS officials have undertaken efforts to implement it. As of May 1999, Fallon NAS had lined 16,419 linear feet of irrigation ditches and leveled 347 acres of fields at a cost of about $655,000. This cost was in addition to an estimated $817,000 spent on studies and pilot projects. According to the officials, the implementation of this strategy has stalled because of excessive costs and a shortage of funds. In 1998, Fallon NAS advertised a contract to line another 45,000 linear feet of ditches with concrete and level another 800 acres of fields. Fallon NAS originally estimated the cost of the additional work to be $1.4 million, but the lowest bid it received for the work was $1.9 million. According to Fallon NAS officials, because of the excessive costs, a shortage of funds, and concern that the work would save what they believed would be a relatively small amount of water, this contract was not awarded. Hence, Fallon NAS' chosen land management strategy is not currently being fully implemented.