An estimated 6,000 new homes will be built in rural Yakima County over the next 20 years.

Sooner rather than later — perhaps within a year — those future homeowners will need to do more than line up financing, select a builder and deal with the various issues that come with building a home.

They will have to buy water. More specifically, the right to use water.

Future domestic wells must avoid impacting senior surface water rights because of a court decision that counties must protect water resources under the state Growth Management Act, and a federal study that found groundwater and surface water are connected.

Rights to all the surface water currently belong to someone else: the Yakama Nation, early settlers, and farmers in the Yakima Irrigation Project. Those rights date to 1905 and earlier.

The county’s authority to require new homes to secure water rights before building — and a strict limit on how much a well can draw — will trump the existing state exemption for domestic uses of 5,000 gallons per day. In a drought, wells drilled under the exemption could be ordered to shut off to protect the senior rights.

In response, Yakima County officials are planning to use economic development funds to create a countywide water utility to purchase senior water rights and sell portions of those rights to prospective homeowners when they apply for a building permit. The revenue from permits will be used to purchase additional water rights to sustain rural development beyond 2033.

“This is a paradigm shift in the way we do business,” said Yakima County Commissioner Mike Leita. “When and how this will be resolved is yet to be seen. It is not a question of if. We have passed that threshold.”

Many details, including how much access to water will cost, are still being worked out. Usage will be limited to 350 gallons per day, considered the average amount for a household.

Homeowners will have to install meters to measure their use and report that use to the county’s water utility.

City dwellers are not affected by the county’s fledgling program.

Joe Walsh, government affairs director for the Central Washington Home Builders Association of Yakima, said he expects the new procedures will add more time and cost to obtaining a building permit.

“There will be some delays at the beginning of the process of getting a building permit. Hopefully, they won’t have anything that is unreasonable,” he said.

“This is a dramatic change, but we have seen this coming since 2007. It is inevitable,” Walsh added.

But different approaches are being considered in the other two counties that make up the Yakima River Basin, Kittitas and Benton.

The differing stances are the result of the failure of a basinwide coordinated approach among all three counties advanced by the state Department of Ecology and the agency’s regional director, Tom Tebb. His plan also included a $2 million state appropriation to purchase water rights for use in all three counties. But criticism about government competition with private-sector water banks already in existence led to the funding being dropped from the budget.

Kittitas County commissioners are pursuing a plan that will cap daily water usage at 350 gallons per day but not require homeowners to purchase a share of a senior water right — a position not likely acceptable to senior water right holders or the state Department of Ecology.

Commissioner Paul Jewell argues the county’s stance imposes stricter limits on access to water than anywhere else in the state and would comply with Growth Management Act requirements that counties protect water resources. The county now has until October to submit changes to its development regulations that the Supreme Court in 2011 found out of compliance in regard to protecting water. The state high court found the county hadn’t done that in approving rural subdivisions.

“The Supreme Court said growth management requires the counties to regulate to some extent beyond the state law with regard to protecting surface and groundwater resources,” he said. “That is what we are proposing to do, and we are going further by limiting how much can be withdrawn.”

The proposed requirements would apply in lower Kittitas County. In the upper county, a moratorium on new wells without offsetting the new use with a share of a senior right has been in place since 2009. The ban spawned private water banks to sell water that can cost up to $10,000 for a share of a senior right.

Benton County, with arguably a portion of its land base outside the geographic confines of the basin, would prefer to place the business of providing water in the hands of private business.

Commissioner Jerome Delvin, a former state legislator, said his county would prefer not to be a water cop. The future would rely on developers providing proof they have a legal right to water for their project before county approval is given.

“It is as simple as saying, ‘Go find a water right,’” he said.

County officials plan to gather together builders, Realtors, and health and conservation districts late this month to start talking about how to comply with the requirement to avoid affecting senior water rights.

While disappointed with the collapse of the three-county talks and the state money to purchase water rights, Ecology’s Tebb said he believes the counties have a greater awareness of their obligations and the risks associated with continuing to allow groundwater withdrawal that is not backed up by a senior water right.

“We are one drought away from this issue being front and center once again,” he said.