As churches and other groups move into industrial areas--looking for cheaper land and bigger spaces--the city loses potential space for future business development that would have contributed tax revenue to the city.

City staff hopes to solve the problem by rezoning some industrial and residential areas and setting more specific guidelines governing where different uses can be located.

The city would rezone residential land with places of assembly on it as "public facilities," essentially setting it aside for that use.

The other zoning change concerns the creation of combined districts where recreational uses are compatible with surrounding industrial uses. Places of assembly would be able to move into these areas.

On March 6, the Sunnyvale Planning Commission unanimously approved staff's plan, and on March 21, the issue goes before the city council for final approval.

As property values and population have risen in Sunnyvale, the demand for large spaces to house gyms, churches and educational facilities has increasingly led companies to look for vacant space in industrial zones.

"We've been doing this for a lot of years, with a lot of councils, and it's beginning to catch up with us," said frequent meeting watcher Harriet Rowe.

As Sunnyvale prepares itself for the forecasted economic upswing and resurgence of business, the planning commission and city council are becoming increasingly concerned about making sure the supply of space will meet the demand.

On Sept. 20, the council enacted the moratorium to give the city time to study the issue and come up with an overarching solution.

"We want to provide opportunities for these [recreational] uses in the city," said principal planner Andrew Miner, "but you don't want to have an arbitrary placement of them that will in essence take up all your industrial space."

According to the city staff report presented to the planning commission, from 1995 to 2001, there were only five such applications, but since 2002, there have been 36, 14 in 2005 alone. In addition, the city receives 11 inquiries each week related to these uses.

One reason for this, staff points out, is that the price of industrial land is cheaper than land in residential areas, so when churches need to expand, they often look at new locations entirely, not expanded residential campuses.

New zoning would also help the city avoid mixing incompatible businesses.

The need to separate incompatible uses is a common problem because industrial facilities can have toxic chemicals on their properties, and recreational users tend to have children and other "sensitive receptors" on theirs. Council members and city staff have repeatedly said that the primary function of zoning is to prevent incompatible uses from impacting each other.

The issues goes before the city council at its March 21 meeting at 7 p.m. in city council chambers, 456 W. Olive Ave.