AskChesapeake

How much water does the natural gas industry use in the Haynesville Shale?

Water is an essential component of Chesapeake’s deep shale gas development. Chesapeake uses water for drilling, where a mixture of clay and water is used to carry rock cuttings to the surface, and to cool and lubricate the drillbit. Drilling a typical Chesapeake Haynesville Shale gas well requires approximately one million gallons of water.

Water is also used in hydraulic fracturing, where a mixture of water, sand and other additives are pumped under high pressure into the deep shale to create small fissures, or fractures, in the rock which allow natural gas to flow. Hydraulically fracturing a typical Chesapeake Haynesville horizontal deep shale gas well requires an average of three million gallons of water. Normally, a hydraulic fracturing operation is only performed once during the life of a well.

Louisiana has an abundance of water, and the volume of water necessary to drill and fracture Haynesville Shale wells represents a very small percentage of the total water resources used in the region of Northwest Louisiana and Northeast Texas. The total water use in the Haynesville Shale area in 2005 was approximately 90 billion gallons. The natural gas industry is expected to increase the amount used by less than 1.5%, which is well within the available resources in the region.¹  Further, while an average Haynesville Shale gas well uses approximately four million gallons of water, this is the equivalent of the amount of water in the Red River which flows past Shreveport every 41 seconds. Water used in Chesapeake Haynesville deep shale gas differs most notably from all other uses because it is temporary, occurring only during the drilling and completion phases of each well. Use of this water does not represent a long-term commitment of the resource in the Haynesville Shale area.

Where does this water come from?

Chesapeake works collaboratively with regional, state and local agencies to ensure that water used for deep shale gas development is consistent with water use plans, and does not adversely affect other users. Chesapeake utilizes a variety of water sources during Haynesville Shale gas exploration, including rivers, bayous, ponds, lakes and groundwater wells. Chesapeake is reviewing the use of a variety of other water resources, such as treated discharge water from industrial or city wastewater treatment plants, power plant cooling water, marginal (saline) groundwater and the re-use of fracturing water. When drilling inside city limits, Chesapeake often works directly with local officials to arrange water purchases from a municipality.

What is hydraulic fracturing, or “fracing?”

Hydraulic fracturing, commonly referred to as fracing, is the process of creating small fissures, or fractures, in underground formations to allow natural gas to flow. Variables such as the surrounding rock formations and thickness of the targeted shale formation are studied by scientists before fracing is conducted. The result is a process that optimizes the network of fractures and keeps them safely contained within the boundaries of the deep shale gas formation.

In Chesapeake’s deep shale gas plays, water, sand and other additives are pumped under high pressure into the formation to create small fractures. The fluid is more than 99% water and sand, along with a small amount of special-purpose additives.² The newly created fractures are “propped” open by the sand, which allows the natural gas to flow into the wellbore so it can be collected at the surface. The fractures typically extend only a few hundred feet from the wellbore. Normally a fracing operation is only performed once in the life of a deep shale gas well.

What chemicals are used in fracing?

More than 99% of the fluid used during fracing consists of water and sand. Other typical ingredients include a friction reducer, gelling agent and antibacterial agents. A list of a typical deep shale fracturing mixture is below:³

Fracturing Ingredients

Product Category	Main Ingredient	Purpose	Other Common Uses
Water	99.5% water & sand	Expand fracture and deliver sand	Landscaping and manufacturing
Sand		Allows the fractures to remain open so the gas can escape	Drinking water filtration, play sand, concrete and brick mortar
Other	approximately 0.5%
Acid	Hydrochloric acid or muriatic acid	Helps dissolve minerals and initiate cracks in the rock	Swimming pool chemical and cleaner
Antibacterial agent	Glutaraldehyde	Eliminates bacteria in the water that produces corrosive by-products	Disinfectant; Sterilizer for medical and dental equipment
Breaker	Ammonium persulfate	Allows a delayed break down of the gel	Used in hair coloring, as a disinfectant, and in the manufacture of common household plastics
Corrosion inhibitor	n,n-dimethyl formamide	Prevents the corrosion of the pipe	Used in pharmaceuticals, acrylic fibers and plastics
Crosslinker	Borate salts	Maintains fluid viscosity as temperature increases	Used in laundry detergents, hand soaps and cosmetics
Friction reducer	Petroleum distillate	“Slicks” the water to minimize friction	Used in cosmetics including hair, make-up, nail and skin products
Gel	Guar gum or hydroxyethyl cellulose	Thickens the water in order to suspend the sand	Thickener used in cosmetics, baked goods, ice cream, toothpaste, sauces and salad dressings
Iron control	Citric acid	Prevents precipitation of metal oxides	Food additive; food and beverages; lemon juice ~7% citric acid
Clay stabilizer	Potassium chloride	Creates a brine carrier fluid	Used in low-sodium table salt substitute, medicines and IV fluids
pH adjusting agent	Sodium or potassium carbonate	Maintains the effectiveness of other components, such as crosslinkers	Used in laundry detergents, soap, water softener and dishwasher detergents
Scale inhibitor	Ethylene glycol	Prevents scale deposits in the pipe	Used in household cleansers, de-icer, paints and caulk
Surfactant	Isopropanol	Used to increase the viscosity of the fracture fluid	Used in glass cleaner, multi-surface cleansers, antiperspirant, deodorants and hair color

What is produced water?

Water naturally exists in the Haynesville Shale formation. Water that comes to the surface during flowback operations and with the natural gas during production is called “produced water.” Produced water is primarily concentrated, naturally occurring saltwater. While the, flow rate does begin with a high production, it quickly decreases to only a few barrels of produced water per day after the first month of operation.

¹ USGS Estimated Use of Water in US, County Level Data for 2000

² US Department of Energy - “Modern Shale Gas Development in the United States. A Primer” – Page 61

³ US Department of Energy - “Modern Shale Gas Development in the United States. A Primer” – Page 63