When snow early this month forced postponement of a major swimming meet scheduled at Montgomery College by Montgomery County high schools, officials found they had to cancel the event altogether. The reason: There were no unreserved swimming pool time anywhere in the county for the rest of the winter.

Some Montgomery high school swimmers must travel as much as 35 miles round-trip to a pool for their regular one-hour practices. The members of nine high school teams get up between 4:30 and 5 a.m. to practice before school, and members of four other teams practice after 8 o'clock at night. None of the county's 22 high schools has its own indoor pool.

These facts were cited this week in hearings before the Montgomery County Council in support of a proposed $8.6 million aquatic center called for in County Executive Charles W. Gilchrist's $1.4 billion, six-year capital construction program.

"The problems are not limited to high-school swimmers," said Edward J. Gannon, a supporter of the aquatic center. He said the need for such a center has been debated in Montgomery County for the last decade.

"The Red Cross has trouble finding pool time for water safety instruction.

Senior citizens, handicapped individuals, Girl Scouts and all groups run into the same problem as do residents who want to swim for fun and exercise," Gannon said.

The aquatic center is one of 850 projects included in Gilchrist's capital improvements budget ranging from library expansions to Metro-related projects to parking lots. The program contains $86 million in road improvements alone.

Completion of the new county government center, which will have cost $41.6 million by the time it is finished in the spring of 1981, also is included in the budget. The complex includes a new 15-story government headquarters building and a 10-story courthouse in Rockville. It will accomodate more than 1,300 county employes who now occupy rental quarters at an annual cost of $1.1 million.

Other proposals for fiscal 1981 include construction of a new fire station in Germantown, relocation of another fire station in Takoma Park, and the combination of two stations in Silver Spring. The county's fifth police district station is scheduled for opening in Germantown next week, but payments will still be made under the Gilchrist-proposed Capital Improvement Plan.

A landfill, earmarked for Laytonsville south of Riggs Road between Laytonsville and Zion roads, has drawn strong opposition from nearby residents. County officials say privately they expect it will face a court challenge before going into operation.

New libraries are also scheduled for construction in Gaithersburg, Olney and Potomac.

In recommending the $1.4 billion construction program to the council, Gilchrist called the package "relatively austere," and said it represents an effort to "maintain basic services and to limit service level increases."

The proposed aquatic center in the package would contain a 50-meter Olympic-size pool, a separate deep-water pool for diving, a smaller pool for handicapped persons and an outdoor pool with a wave-making machine. There also would be shower and changing facilities.

Because of the cost of the project, the measure faces the possibility of being petitioned to referendum should the council approve it. Under an amendment to the county charter approved by the voters in 1978, any capital construction project costing more than $4.5 million can be petitioned to referendum unless the council passes it as an emergency measure. At $8.6 million, the aquatic center is nearly twice the ceiling.

In testimony before the council, Gannon urged that the aquatic center be located in the vicnity of the Capital Beltway and Rte. 270 with relatively easy access from all sections of the county.

In Gilchrist's Capital Program, $30,000 is earmarked in fiscal 1981 for site selection and design of the center, with construction to begin no sooner than early summer of 1982. Construction would take about two years.

After three public hearings on the program, the council now begins a series of work sessions on the plan, with final action due by May 15. The council can either add to or delete projects submitted by Gilchrist.