Suburban Maryland's water and sewer agency, after being told by county councils to build either "esthetic" water storage tanks - or tanks hidden from view - has announced plans to build a "big blue marble" in Montgomery County.

Late next year, a two million gallon storage sphere will be completed on the campus of Montgomery College in Bermantown. It will be painted on the outside to resemble the astronaut's view of the earth from the moon.

The paint job alone for the big blue marble will cost $140,000 - roughly twice the cost of painting the tower the traditonal green, silver, or rust.

"This is a trend all over the country," said Arthur Brigham, public affairs director for the Washington Suburban Sanitary Commission which has chosen the Germantown project for its first such venture in the area.

Robert C. Haven, director of the WSSC's engineering department, said that hidden water tanks were not the answer because "when the leaves fell, the towers weren't hidden any longer.

The alternative, which the WSSC has chosen for two additional projects, is an underground tank topped by a park. However, the cost is greater than above-level tanks because water must be pumped through the system rather than moving by gravity.

The big blue marble for Germantown will stand eight feet above the ground on a pedestal near a parking lot and fill and empty hydraulically. Consequently, the WSSC will save $1.5 million in operating costs because water will not have to be pumped to and from an underground facility.

For the reason alone, Brigham said, the expensive paint job is worth it. The entire project, awarded to Chicago Bridge and Iron Co. of Philadelphia, will cost $1.7 million. We hope "we can convince people that water storage can be attractive," Haven said.