Editor’s note: For August, Brian Greenspun has invited some members of the community to talk about the issues important to them. Today’s column is by John Entsminger, general manager of the Southern Nevada Water Authority.

When Lake Mead was created in 1935, it made history. Hoover Dam had tamed the wild and unpredictable Colorado River, creating the nation’s largest man-made reservoir and establishing a bank account of water resources that has supported the American Southwest ever since. But just last month, Lake Mead made history once again when, because of the ongoing drought plaguing much of the Western United States, the level of the lake reached a historic low mark. Today, the reservoir that provides 90 percent of Southern Nevada’s drinking water is filled to just 39 percent of capacity; meanwhile, forecasts by the federal Bureau of Reclamation indicate that Lake Mead is likely to decline another 4 to 10 feet by the end of 2015.

This drop in Lake Mead’s water level could trigger a federally declared shortage within the next four years, at which point Nevada and Arizona would be required to temporarily reduce their use of Colorado River water. Nevada’s allocation, by far the smallest of all states, is less than 2 percent of the annual flow of the river. For Nevada’s part, the first level of shortages would cut our 300,000 acre-foot allocation by 13,000 acre-feet — enough water to serve more than 40,000 Las Vegas households.

But thanks to your efforts, our community has already conserved more than enough water to absorb these shortage levels without the need for additional water restrictions. Working together over many years, we have decreased our consumptive water use by one-third since 2002 despite a population increase of about 480,000 people during that time. Per capita water consumption decreased by nearly 40 percent during that period. Adhering to mandatory watering schedules and removing water-thirsty grass, along with our community’s comprehensive system of water recycling and reuse, have greatly reduced our consumptive water use. And it is important to note that we have not yet reached the point of diminishing returns on our conservation efforts, which will continue to produce further reductions in our consumptive use of water.

However, conservation to support the Colorado River system is not solely the responsibility of the residents of this valley. The drought is affecting the residents of all seven states that share the river, and we must continue to work together to identify creative solutions to ease the drought’s impact.

We recently initiated a pilot conservation program in conjunction with the Bureau of Reclamation, Arizona, Denver and Southern California; the program will compensate farmers, cities and industrial water users who reduce their consumption. One fact that is not well known is that less than 20 percent of Colorado River water is used by cities; the largest use of the water is for agriculture. The water conserved by this agricultural, urban and industrial conservation program will remain in lakes Powell and Mead, and will not be used by any of the funding agencies.

We will continue to work with our partners on the Colorado River to extend and protect the water resources that we all rely upon. But as far-reaching as these issues are, we’re not going to forget that, as a nonprofit agency, Southern Nevada Water Authority’s only shareholders are the residents and businesses of Southern Nevada. With this foremost in mind, the agency convened a 21-member panel representing a diverse array of community stakeholders to provide direction in navigating these difficult issues. This committee is studying potential options for additional water conservation measures, infrastructure and long-term resources.

As I write this, Lake Mead’s surface is only 30 feet above our first intake and 80 feet above our second; however, a third intake more than 200 feet below the lake’s current surface level will begin delivering water to the valley late next year. Our engineers are developing options for an additional pumping station to support the new intake and allow us to continue to draw water from Lake Mead even if the surface level declines dramatically. These options will be presented to the citizens committee for consideration.

The issues we face on the Colorado River are difficult and unprecedented, but they are solvable. It is important for the community to understand that decades of hard work have given us options, even in a worst-case scenario of a continued decline in Lake Mead. There may well be difficult decisions to make, but as a community we are well-positioned to meet these challenges.

John Entsminger is general manager of the Southern Nevada Water Authority.