Rep. Ronald V. Dellums (D-Calif.) was elected chairman of the House District Committee yesterday.

By a vote of 229 to 16, the House Democratic Caucus elevated Dellums from the No. 2 spot on the committee to succeed convicted Rep. Charles D. Diggs Jr. (D-Mich.).

The five-term representative from Berkeley said last night that he is "staunchly committed to full implementation of home rule" for the city.

Dellums, 43, said "Washington can and should be an environmental and cultural beacon, a true model for what all our urbna areas ought to be..."

Dellums said he would meet Friday with Mayor Marion S. Barry "to discuss developing new programs to meet d.c/. needs.

D.C. Del. Walter E. Fauntroy said he expects "more vocal leadership" with the outspoken Dellums as chairman, which "may reflect in more aggressive legislation to expand homerule powers of the District and to honor legislative initiatives by the local elective government."

Rep. Herbert E. Harris II (D-Va.), chairman of the District subcommittee on economic development and regional affairs, also said he expects Dellums to be "active, out front." He praised Dellums as "extremely bright, articulate, vigorous."

The one cautionary note sounded by several House members related to Dellums' sponsorship in the past of legislation that would allow the city to impose an income tax on suburbanites who work in the District.

Harris and other House members from the Washington suburbs who usually are strong supporters of District legislation in Congress have warned that efforts to impose a commuter tax -- barred by legislation that gave the District partial home rule seven years ago -- could imperil area cooperation.

An issue of overriding concern to all area jurisdictions is how far the federal government will go in financing the $1 billion needed to complete the 100-mile Metro rail system.