In an attempt to insure that the Colesville-Fairland area of Montgomery has adequate water pressure, the Washington Suburban Sanitary Commission (WSSC) will build a 1 million gallon water storage facility on part of the site formerly planned for Colesville Junior High School.

The first underground water storage tank in Montgomery County; the facility will increase the county's current usable water storage capacity of 45 million gallons by about 2 per cent and thus better protect residents in the case of a water system breakdown such as the one last week.

Linda Fohs of the county environmental planning office said the tank is designed both to increase the county's overall water storage capacity and to increase water pressure for the distribution lines in the Colesville-Fairland area. That area in northeast Montgomery County has occassionally experienced low water pressure, she said.

The Colesville tank has been planned since 1972, but was held up when area citizens protested a planned above-ground tank as unsightly. Their protest led to two studies and a 1973 county council policy directing that all new water tanks be built underground or partly underground.

The new water tank is expected to be completed in late 1978. Approximately 10 other new water storage facilities, most of them to be underground tanks, are planned for Montgomery County in the next 10 years.

The new tank will be located at New Hampshire Avenue and Notley Road, on part of the tract planned for the junior high school. The Montgomery County school board recently gave the land to the county because new population projections show the school will not be needed.

The county is giving the land required for the water tank to the WSSC in return for a nearby 1.3-acre tract that it originally acquired for an above-ground water tank. Tom Stone, county site selection planner, said the underground tank will take up about four to six acres underground, but the WSSC will retain only one-half acre above-ground.

The rest of the 18.8-acre undeveloped junior high school site will be sold for half-acre subdivision lots when the sewer moratorium has eased in a few years, Stone said. He said he expected the land would bring the county $12,000 to $15,000 an acre.

In a related matter, the county plans to retain the 15-acre Colesville Elementary School property which the school board also gave it.The school closed this June.

Stone said the school building will be used for county offices and the existing tennis courts and other recreation facilities will probably be kept.The 1.3 acres acquired from the WSSC is next to the elementary school site, and may be used for parking.