In a case that bristles with far-reaching implications, the Navajo Nation has sued the federal government in an effort to obtain recognition of tribal claims to Colorado River water. A consideration of such rights could result in a rethinking of current state and federal water management policies and practices.

If, in fact, there were any doubts about the matter, negotiations now underway to settle Navajo water right claims could serve as a case study of the intricate and complex workings of water law. What further complicates the issue in this instance is that the area of the Navajo Nation to receive water from whatever settlements are worked out is located close to the boundary between the upper and lower Colorado River basins. The Law of the River, which determines the management and use of Colorado River water, including its allocation between basins, becomes an issue to be reckoned with.

Snow might be one of the ways to differentiate the sensibilities of hydrologists from others not sharing their professional interest. Whereas non-hydrologists may see the photo at right as a lovely snow scene hydrologists viewing the winter landscape may think of the problems of measuring snowpack to determine spring runoff.

The first World Water Monitoring Day will be held Oct. 18. From Sept. 18 to Oct. 18, citizens throughout the world will be monitoring the quality of their local watersheds and entering the results into an international database. World Water Monitoring Day is intended as an educational opportunity for watershed leaders, educators and trained volunteers throughout the world to help citizens better understand the workings of a watershed.

The quest to discover signs of water on Mars continues, with Opportunity, one of the two Mars Exploration Rovers, sending back images of the planet soil. At bottom left of the photo at right is a magnified look at martian soil showing spherical pebbles among the mix of particles. One of the explanations to account for the pebbles' round shape is accretion under water. A mineral map of Opportunity's surroundings offered a more significant sign of water. It indicated concentrations of a coarse-grained hematite. Hematite usually forms in association with liquid water.

When most people think of drought they think of possible personal inconveniences. Should they forego their Lake Powell vacation? Will watering vegetation face restrictions? Will water bills go up? Drought and dry conditions also affect Arizona's wildlife.

The Governor's Drought Task Force, established about a year ago to develop a management plan for drought stressed Arizona, is making progress on its assigned task.

Not likely to be disputed is the premise that a successful water conservation program results in water users consuming less water. What has been disputed - a dispute the Arizona Supreme Court recently resolved - is whether the Arizona Department of Water Resources should regulate water providers or water users to encourage water-saving practices and habits.

Eagerly anticipated and vitally needed, the North American monsoon is also elusive and difficult to predict. When will it arrive? How much precipitation will it deliver? How long will it last? Research is underway to study the workings of the monsoon to find answers to these and other monsoon questions.

Interbasin groundwater transfers are a strategy to obtain additional water supplies in parts of the state with inadequate water resources. It is a strategy, however, fraught with legal obstacles in Arizona due to passage of the 1991 Groundwater Transportation Act and subsequent amendments. Passed in response to rural concerns, the GTA essentially prohibits the transfer of groundwater from one hydrologic basin in the state to another.