NORMAN — Groundwater supplies nearly 40 percent of all water used in Oklahoma, according to John Harrington, director of Water Resources, Association of Central Oklahoma Governments, but people don’t always know whether that water is drinkable before they drill.
The Oklahoma Corporation Commission has had many complaints of water well pollution over the past two decades in and near oilfields. The oilfields that most often create the problem are older fields with activity initiated before 1980, Harrington reported to the Norman City Council at its study session on Tuesday evening.
Nowadays, Oklahoma knows how to prevent saltwater problems associated with oil rigs and natural gas wells, but some old wells are impacting modern water wells.
“We are detecting this saltwater with electrical imaging techniques,” Harrington said of identifying contamination of private water wells.
As many as 295,000 Oklahomans have private water wells and 73 percent of all agricultural irrigation comes from groundwater, Harrington reported.
Recently, a “fairly new gated community in Northwest Oklahoma City” had problems with salt contamination in private water wells, Harrington said.
When a domestic well is drilled, if the piping does not have enough casing to protect it, contamination can occur from oilfield salt water in the shale. That well can lead to cross contamination of the aquifer.
Harrington said requiring casing to run deeper could protect domestic water wells from contamination. Unused water wells should also be “drilled out and plugged to prevent the spread of more contaminants down into the aquifer,” Harrington said.
In an effort to provide more information for well drillers, the Oklahoma Corporation Commission has been mapping old oil wells on Oklahoma Aquifers.
Additionally, water watchdogs want to require protective casing for a depth of at least 30 feet.
“We are making a proposal to the water resources board to amend the drilling standards,” Harrington said.
A primary amendment would add the requirement for deeper casing for water wells.
Meanwhile, Norman is working on updating its water well permitting requirements. While the Oklahoma Water Resources Board regulates groundwater use and issues permits for most wells, cities also are allowed to regulate and permit domestic and industrial wells.
State law limits how much water can be used and the purpose of those uses but does protect the water rights of property owners.
Norman city leaders are concerned that a potential increase in domestic wells in response to the drought could deplete or reduce the water in the aquifer, impacting the water available to the city’s water wells. They also are concerned about contamination of the aquifer.
Proposed city code amendments include:
· Increasing the permit fee from $5 to $50 to cover city costs.
· Updating regulations to come into compliance with state law.
· Using state definitions for domestic and industrial use.
· Adding requirements to protect water supply.
· Monitoring usage through water meters.
“My biggest concern about all this is contaminating the aquifer,” council member Jim Griffith said.
Harrington said how deep a well must go to hit the Garber-Wellington aquifer varies.
“I think it’s absolutely critical that we protect the Garber-Wellington for uses other than drinking,” attorney Harold Heiple said .
He suggested that if a homeowner or entity is hooked up to city water, they should be prohibited from drilling into the aquifer.
Heiple said an HOA representative from Cascade had been told by a driller that he would need to go down 600 feet but the OWRB said the HOA would likely hit good irrigation water around 200 feet — protecting the aquifer and saving the HOA a large amount of money.
Assistant city attorney Kathryn Walker said she is unsure, under current state law, if the city can limit the depth a property owner can drill.
Heiple said when an HOA starts using rights of way and going under city streets to provide water for a swimming pool and irrigation, it is becoming a utility.
“I think it’s time we go to the mat protecting our water,” Heiple said.
Currently, the city code prevents someone from drilling into the aquifer if they are on city water.
Also discussed were tribal water rights in east Norman.
“We would be pre-empted if it’s a federal Indian tribe,” city attorney Jeff Bryant said.
Harrington said if the city is going to meter water on domestic wells, it should occasionally collect data from samples to check for contamination.
“Most people on a domestic well don’t know their own groundwater quality, so the city would be providing a service,” Harrington said. “We know more about the water quality at the municipal level depths than we do at the domestic well depth, so the city would be providing badly-needed data.”
In addition to concerns about saltwater, west Norman also has issues with naturally-occurring arsenic.