Water use for hydraulic fracturing (fracking) in Colorado is expected to grow by 35% by 2015, but it will remain a minute portion of the state's overall water use, according to a report by a trio of state agencies, including the Colorado Oil and Gas Conservation Commission (COGCC).
COGCC and the state's Division of Water Resources and Water Conservation Board took on the task of answering policymakers' questions about how much water will be required by the increased use of fracking as part of the state's ongoing shale oil and gas exploration and development (E&P). The short answer is it is not easy to predict, but in the larger statewide use of water it is no more than 0.1% of the state's consumption. Agriculture is the big user.
The report starts from the point of view that predicting future levels of oil/gas well development is very difficult because of several frequently changing variables, such as the national and regional economies, energy prices, capital availability and technological innovations. Therefore, the analysis and estimation of future water needs for horizontal drilling activities made a number of assumptions, one being that demand for new wells will remain relatively flat, something that has not happened the past five years.
For the purposes of estimating water usage, however, the report's authors assumed a 20% annual growth rate in horizontal drilling, with a flat demand environment and a declining growth in conventional vertical well drilling. Based on these and related assumptions, the projected annual demand for fracking water moves from 13,900 acre-feet (one acre-foot equals 326,000 gallons) in 2010 to 18,700 acre-feet in 2015.
Water usage growth is estimated to be about 1,200 acre-feet this year, moving up to a total of 16,100 acre-feet for fracking, compared to 14,900 acre-feet last year.
"Regional geology dictates how wells will be drilled, either vertical or horizontal, and the volume of water that will be necessary to provide the most effective fracture stimulation treatment," said the report, "Water Sources and Demand for the Hydraulic Fracturing of Oil and Gas Wells in Colorado from 2010 through 2015."
To add perspective, the report stated that Colorado uses about 16.35 million acre-feet annually, with agriculture accounting for 13.9 million acre-feet, or 85.5% of the state's water use.
The report also looked at potential sources of water for fracking and listed 10 separate ones, noting that the preference should be for reuse and recycling of water, and one of the 10 identified sources was this category of water from well construction water.
"For all of the different sources used for well construction, the water right in question must contain provisions that allow the water to be fully consumed," the report said. "Under that scenario, water used for well construction of one well may be recovered and reused in the construction of subsequent wells."