In the above satellite image taken June 29, 2017, water bodies show up in deep shades of blue. Rivers and lakes are discernable as well as hundreds of smaller waterbodies like ponds, streams, and the rectangular water impoundments associated with oil and gas operations. The image also depicts healthy vegetation in shades of red and mauve and less vegetated areas in shades of green. Looking at the image one might get the impression that water in Oklahoma is plentiful, but, in truth, our state’s water resources are being stressed by the growing demands for fresh water. Furthermore, according to the Oklahoma Comprehensive Water Plan updated in 2012, demand is expected to grow nearly 30% through the year 2060. As activity in the STACK and SCOOP grow, operator’s requirements for fresh water will be driven by the increased need for horizontal drilling, extended laterals, and up-sized completions. In this scenario, insufficient supplies of water for oil and gas production will put additional strain on already tight drilling and completion budgets as well as negatively impact the state economy as production tax revenue declines.
This article will be the first of a short series in which we’ll examine the relationship between water resources and oil and gas operations in Oklahoma. As usual, I’ll be exploring several geographic questions to guide us through our investigation of this topic. For example:
- Where does the water come from that’s used in O/G?
- Where is there potential for new water sources?
- Where are the highest areas of water usage in Oklahoma?
- Where are there heightened risks of water shortages?
- How does water used for drilling and fracking get to where it’s needed?
- Where does the water produced (and used) during drilling and fracking end up?
Sources of water for oil and gas operations
Let’s begin by looking at the sources and uses of fresh water in our state. First, a definition of two key terms. There are 2 basic types of fresh water: surface water and groundwater.
- Surface Water– The most obvious sources of water are those we can see on the land surface such as those depicted in the image above. Surface waters include streams, rivers, lakes, reservoirs, and freshwater wetlands. Because these sources are on land, they are easily developed for uses such as drinking water, crop irrigation, livestock production, industry, and, of course, oil and gas. Surface waters are often thought of as renewable resources because of their dependence on the earth’s water cycle. The amount of available surface water changes constantly due to inflows and outflows. So, the amount and location of these waters continually change over time and space. The map below depicts our state’s major watersheds, lakes, rivers, and streams. You’ll notice many of these features are within areas of oil and gas operations such as the STACK, SCOOP, and Arkoma Basin.
There are several factors affecting the availability of surface water for human use:
- Precipitation amounts
- Seepage from groundwater sources
- Surface to groundwater movement
- Human withdrawals
The map below from the U.S. Drought Monitor illustrates the drought status of Oklahoma counties the week of July 18, 2017. As we head into the warmest (and driest) part of our summer, we can expect the map to reflect much drier conditions. If you’re interested, you can track this yourself at http://www.owrb.ok.gov/drought/index.php
The Oklahoma Climatological Survey http://climate.ok.gov/also publishes maps and data on precipitation in the state. Current maps from their site are below. The STACK counties are well below percent of normal precipitation. Blaine and Kingfisher counties are in the bullseye where rainfall is well below normal.
- Groundwater – Water beneath earth’s surface is groundwater. Under most land masses there is some amount of water, yet, like surface water, amounts can vary over time and space. Groundwater also varies by depth from just beneath the surface to hundreds of feet below. Groundwater is created by the infiltration of surface water from precipitation through the soil and down into layers of saturated rock material called aquifers. Due to gravity and the porosity of the saturated rock, water in an aquifer moves slowly downward beneath the surface and may eventually discharge into streams, lakes, and oceans, or withdrawn for human use.
The map below from the OK Water Resources Board depicts the primary aquifers in our state. Two main factors affect the availability of groundwater: precipitation and withdrawals for human use.
Uses of fresh water
There are several competing interests for Oklahoma’s fresh water. By far, most of the water in our state is used to meet the demands of agricultural, municipal, and industrial uses. However, demand for oil and gas operations has been rising since the new millennium.
Oil and gas use a decade ago was around 2.5% of the state’s total water demand and was projected to double by 2060 when the Oklahoma Comprehensive Water Plan (OCWP) updated in 2012. In the meantime, the water demand for oil and gas operations doubled to 5% in 2013 well ahead of the State’s projections and is showing no signs of diminishing. Why the increase? For one, growth in horizontal drilling activity and secondly, the growth of upsized completions requiring more than 2-3 times the typical volumes of a few years ago. With operators drilling faster, and employing longer laterals, completions now require as much as 12 million barrels (1 barrel = 42 U.S. gallons) of water per frack. The graphs below compare water usage and number of horizontal wells drilled since 2000.
Where does the water come from that’s used in O/G?
The Oklahoma Water Resources Board (OWRB) is responsible for managing and improving our water resources, including surface and groundwater, which are both used in oil and gas operations. Operators requiring the the use of these waters must first seek approval from the OWRB by applying for 90-day provisional, temporary permits for drilling and completions which are valid for 90 days. Provisional permits are approved by the OWRB Executive Director and do not require public notice or hearing. As you can see from the graphic below, the amount of water allocated for permitted oil and gas uses trended upward in the years 2004-2013.
Reviews of oil and gas water use permitting trends show increases in:
- reliance on groundwater
- number of permits issued by OWRB for O/G
- number of O/G wells
- volumes of water withdrawn
Once permits have been granted, operators are free to withdraw the amount of surface or groundwater specified by the permit for drilling and fracking operations. The volume of water to be used will vary from site to site due to local geology as well as drilling/fracking methods employed on the site. Occasionally, groundwater can be drawn from the pad site through water wells drilled on site. More often, water is delivered to the pad site via surface or underground pipelines or by tanker trucks. The latter option is the most expensive, especially when upsized completions are planned. The map below shows surface and groundwater provisional, temporary permit locations within key oil and gas areas.
The oil and gas industry was not the only sector projected to consume more water in the OCWP update. Water demands from nearly all sectors were expected to continue rising 50 years beyond the original 2007 plan. To ameliorate predicted fresh water shortages and avoid expensive development of new supplies and water infrastructure, the OK State Legislature passed the Water for 2060 Act (HB 3055) in 2012, establishing a statewide goal of consuming no more water in 2060 than was consumed in 2010. One of the primary vehicles for achieving this goal will be water recycling and reuse. So, what implications does this have for operators in our state? In short, the answer is plenty. Water recycling and reuse is already becoming a common practice as my recent research has shown numerous strategies and technologies aimed at reducing the cost of water and maximizing its use in the oil field.
As part of the Water for 2060 initiative, several working groups were formed to study options for meeting the state’s goals for water use. Among the groups formed was the Produced Water Working Group (PWWG) who studied options for reusing and recycling water produced from drilling and fracking operations. We’ll take a closer look at this topic as part of this series. In the meantime, you can see a summary of their recent findings at http://www.owrb.ok.gov/2060/PWWG/Study_2_Page_Handout.pdf
Given the increasing use of fresh water in the state and the risks associated with dependence on groundwater, other sources of water for oil and gas operations in our state are needed. More on that in the next article. As always, I’m here to answer your “Where?” questions. Reach out to me at [email protected]
OK Water Survey, University of Oklahoma – May 2015
OK Water Resources Board
US Geological Survey
Julie Parker has a decade of experience serving the Energy industry where she became an expert in the integration and application of geospatial technologies to exploration and production projects and workflows. Ms. Parker entered the industry in 2006 when she became the first GIS Director for Chesapeake Energy, a large independent producer of natural gas headquartered in Oklahoma City, Oklahoma with operations throughout the U.S. During her tenure at Chesapeake, Ms. Parker built and lead a robust, cross-functional GIS department that gained a reputation for developing and deploying leading edge solutions for nearly all areas of the company.