A Virginia legislative committee approved a new reapportionment plan for the House of Delegates yesterday amid threats by civil rights groups that it is certain to be scuttled by either the Justice Department or a federal court as were the legislature's previously enacted plans.

The latest plan, adopted 16 to 3 by a House Privileges and Elections Committee, will be voted on Monday by the General Assembly when it reconvenes in Richmond. The legislature is under a court order to redraw its House district to reflect population changes shown by the 1980 Census.

"We are close to the numerical goals. I hope we have met the requirements of the court with this plan," said Del. John Gray (D-Hampton), the committee chairman.

Advocates of civil rights groups, however, argued that the plan did neither. "They have just taken the express route to court," said Judy Goldberg, a lobbyist with the American Civil Liberties Union. She said the new plan has too many multimember districts, too great a population variance between districts and dilutes black voting strength in the state.

Northern Virginia's House districts remain unaffected by the new plan which has a population variance between districts of slightly more than 10 percent.

The legislature's first House redistricting plan was rejected by Justice last summer on the grounds that it diluted black voting strength in violation of the 1965 Voting Rights Act.

Virginia lawmakers redrew the plan only to have it challenged in federal court. Last August a three-judge federal panel ruled that the plan violated the Constitution's guarantees of equal representation because the difference in population between some districts was as high as 26 percent.

The court allowed House elections under the plan Nov. 3, but ruled a new plan must be approved by Feb. 1 or the court would impose one of its own.

The new redistricting proposal calls for 46 House districts instead of the 52 under the 1971 plan. Only 12 of those districts contain a single delegate.