Hydraulic fracturing in Colorado uses enough water annually to meet the needs of as many as nearly 300,000 people, according to a report released in June by Western Resource Advocates.

The report uses Colorado as its reference case. Fracking operations in the state use between 22,100 and 39,500 acre-feet of water per year -- on the low end, that's roughly equal to the yearly water needs of Lakewood, Colo., and on the high end, it's about the same amount of water one of Colorado's most populous counties would use in a year.

One acre-foot is approximately equal to a football field, minus the end zones, covered in a foot of water -- and one acre-foot can serve the needs of two to four families for a year.

Oil and gas industry folks tend to discuss their water needs by comparing them to agricultural uses, which makes their percentage use appear much smaller, but because much of the new drilling on the state's Front Range is tied to municipal water supplies and is occurring in proximity to population centers, water use comparisons should be made with municipal, not agricultural uses, the report says.

Hydraulic fracturing operations in Colorado are being developed closer and closer to population centers, and water from fracking can't be returned to groundwater supplies because it contains potentially harmful chemicals. Instead, fracked water must be disposed of in underground wells or pits, according to the report.

"Oil and gas wastewater is of such poor quality that it cannot be returned to streams. This differs from most other water uses, which create return flows that are used downstream and that benefit aquatic ecosystems along the way," the report says.

For comparison's sake, over 90 percent of residential water eventually makes its way back into groundwater supplies.

In Weld County -- the state's ninth most populous county and its leading producer of cattle, grain and sugar beets -- the report estimates fracking uses one- to two-thirds as much water as the total public and domestic use in the county.

And this year in Weld County -- the largest agricultural county in the state and the eighth largest in the U.S., and where over 50 percent of new gas wells in Colorado were drilled last year -- hundreds of acres of corn are dying from drought and farmers are selling off their cattle early because they don't have enough feed and water to maintain them.

The report stresses that "oil and gas development must be done in a deliberate and responsible manner that protects Colorado communities and the environment from the outset. Colorado cannot afford to continue developing new oil and gas wells without understanding the associated water needs in order to determine if the water is available or if we are over-allocating this resource."

The report says that the state needs to plan and get it right before large-scale drilling continues unabated, because the state's oil and gas resources aren't going to disappear; it calls for more comprehensive and publicly available data on oil and gas water demands and water supplies.

It also recommends that produced water from fracking operations should be recycled as much as possible to minimize the industry's water needs.

The report says that the oil and gas industry should be required to submit well-specific data to the state, including the volume of water to be used for drilling and fracking, recycled water, and source and type of water supplies. The information should be publicly available in a searchable format.

Minimum residential setbacks should also be increased to protect public health. Currently, state law requires only a 350-foot setback for oil and gas drilling operations. Setbacks for riparian areas should also be increased, the report concludes.

The state should also adopt a rule for baseline water quality testing and ongoing monitoring, using tracers to track the movement of chemicals and other fluids. Comprehensive plans should also be required by the state for fracking operations, with the aim of protecting public health and the environment.

Drilling and fracking also raise air quality concerns. Another study cited by the report found that increases in Denver-Julesburg oil and gas well development are the most likely source of escalations in ozone-forming air pollutants and unusually high levels of hydrocarbon emissions along the Front Range, which is already an area in violation of the EPA's summer ozone pollution standards.

Another recent study in Garfield County, the report notes, found that chemicals from drilling and fracking pose neurological and respiratory health risks to people living within a half-mile of a drilling site.

The report also says that recommendations from the State Review of Oil and Natural Gas Environmental Regulations should be followed, including: maximum and minimum surface casing depths for the extent of the pipe and casing inserted into the ground during drilling, to seal the wells off so they can't contaminate water aquifers; requiring well completion reports, which are essential for determining whether any problems with fracking may threaten groundwater, and those reports should include identification of materials used, including aggregate volumes of fracking fluids and proppants and the fracking pressures recorded; and the evaluation of naturally occurring radioactive wastes associated with fracking.

The lead author of the report, Laura Belanger, the water resources and environmental engineer with Western Resource Advocates, said that "it's clear that we need to take a step back and make sure we aren't over-allocating our most important resource, one frack job at a time.

"While we may need natural gas to transition to a cleaner energy future, we must have water to survive."