If you own a home in southwest Manteca and want to add a room you may have to get the blessing of the Delta Stewardship Council.

That’s a growing fear of just how far the Delta Stewardship Council will go. And it is creating a rare consensus among  leaders,  local government administrators, and private sector movers and shakers throughout San Joaquin County.

The commission is a freestanding, independent state government agency being given powers rivaling the California Coastal Commission and the Tahoe Regional Planning Agency. It has a vast array of powers in what happens not just in the primary Delta zone but the secondary zone that includes all of Lathrop, parts of southwest Manteca, more than half of Stockton and easily half of the county. The commission also has jurisdiction in what happens on the tributaries such as the Stanislaus River that flow into the Delta.

Stockton Mayor Ann Johnston on Tuesday appeared before the Manteca City Council with County Supervisor Ken Vogel and others involved in a countywide coalition Tuesday to sound the alarm.

They admittedly weren’t paying much attention to the Delta Stewardship Council that is in its infancy stages. The council is now essentially drafting rules of engagement when it comes to the task of protecting Delta water quality and working to make sure water needs of entities that depend on imported water from Northern California that passes through the Delta.

But then the commission submitted three written comments on land use projects far from the Delta making it clear that the seven-man body that consists of appointees believed the proposals could impact the Delta. The three projects were:

• A traffic study involving an intersection in Thornton and whether it made more sense to have diagonal or parallel parking along a street.

• A plan to change a subdivision street alignment in Mountain House.

• A proposal to build a recycling center in Stockton.

The Manteca City Council unanimously agreed to join the fray by sending a letter to the Delta Stewardship Commission expressing severe reservations about the intrusion on local land use control.

The letter is in response to a 2,200-page report on the stewardship council’s governance plans that is being circulated for comments. The governance plan essentially will dictate how the commission created by the California legislature’s Delta Reform Act of 2009 will go about reaching its objectives.

The coalition is gearing up for what they expect to be a 12- to 18-month fight to get language in the governance guidelines for the Delta Stewardship Commission to prevent  it from making intrusions into planning concerns within the secondary Delta zone that are clearly local in nature.

Johnston noted cities such as Stockton, Lathrop, and Manteca already must comply with the dictates from the Environmental Protection Agency, the Department of Water Resources, the Department of Fish & Game, the provisions of the California Environmental Quality Act, and a host of other existing state agencies whenever they are considering a development related project.

“My personal belief is that it (the Delta Stewardship Commission) is a way to get more water south,” Vogel stated. He noted it would essentially sacrifice San Joaquin County for Los Angeles’s economic health and water needs.

Vogel praised Southern California efforts to conserve water but added it isn’t enough.

It is why Vogel believes not only do the five Delta counties need to demonstrate they are also good water stewards but they need to fight efforts that would severely hurt the San Joaquin economy in order for enough water to be freed up to meet the growing thrust of users in the southern San Joaquin Valley, the Los Angeles area, and the Bay Area.

One plan connected with a conveyance facility passing through the Delta would be to force 100,000 acres of Delta farmland mostly within San Joaquin County out of production. A conveyance facility is a term used to avoid describing the proposal as a peripheral canal.