Kern County Supervisors introduced sanity into the planning process two years ago when they established a rule requiring most developments in unincorporated metropolitan Bakersfield be hooked up to a municipal sewer system.

Previously, many projects had been allowed to go forward with septic-tank systems. Supervisor Michael Rubio, who has been dealing with sewage oozing from septics in the Rexland Acres area throughout his tenure on the board, was among those who praised the sewer-first rule.

The two-year-old policy has another, perhaps greater benefit. It makes leapfrog development — the practice of hopping over stretches of rural land to build new housing projects — more difficult. Finally, county government had a useful mechanism for keeping developers from creating otherwise unnecessary demands for roads, emergency services and other elements of expensive civic infrastructure.

But the policy has always been controversial because it interferes with the “dreams” of some developers. Builders and speculators just can’t sprout new projects away from basic municipal services, such as sewers. They generally have to wait until more orderly growth eventually reaches them.

Now the Board of Supervisors is planning to reconsider the policy, which requires sewer hookups on parcels of six acres or less.

Today supervisors will weigh whether to weaken the ordinance to require sewer hookups only on parcels of five acres or less. The new, proposed threshold is more significant than it might seem. If it’s passed, it could open the floodgates of development, allowing more densely divided land in areas not served by municipal systems.

Concerns about leapfrog development aside, urban development that relies on septic tanks for sewage disposal threatens metropolitan Bakersfield’s underground water supply.

Supervisor Mike Maggard is the likely swing vote in the debate. Real estate interests lobbied him hard during his 2006 campaign, and at least one believes Maggard will  weaken the ordinance and its protections. The original rule passed 3-2, but last year Maggard replaced Supervisor Barbara Patrick, who supported the rule.

Chuck Lackey, the county’s director of Engineering and Survey Services, says the supervisors have four options: leave the rule alone; have all appeals of staff’s application of the rule reviewed before the board; have supervisors hear all requests for exemptions to the rule; or make the rule less restrictive to development.

Supervisors should leave the rule as it is. Reducing acreage limits will allow more urban sprawl. Creating a system in which staff decisions regarding the rule are reviewed by  supervisors will turn the process into a political one, rather than one based on sound environmental policies and consistent standards.

Kern County supervisors showed courage when they reined in urban sprawl and protected metropolitan Bakersfield’s groundwater by adopting the sewer rule. Let’s hope they will do it again.