The District government, in response to complaints that the city's three juvenile detention centers are understaffed, revealed plans yesterday that call for nearly doubling the number of supervisors at the facilities.

Disclosure of the plan came during a meeting between top city officials and D.C. Public Defender Service lawyers to discuss staffing and housing problems at Marshall Cottage, a dormitory unit at Cedar Knoll detention center that was recently reopened to accommodate an unexpected surge in the number of youths in custody.

After the meeting, Patricia Quann, administrator of the Youth Services Administration, described the District's plan to hire 60 new supervisors for Cedar Knoll and Oak Hill, both in Laurel, and the Receiving Home for Children in Northeast Washington, as "very, very significant".

"We have been chronically understaffed," said Quann, who added that the facilities have had to rely on the use of "extensive overtime."

Other sources closely involved with the detention facilities, however, said the new staffing "doesn't even come close to meeting the needs" at the three facilities. These sources said at least 55 new employes are needed at Oak Hill alone.

In addition to hiring additional supervisors, the District plans other improvements at the detention facilities, according to an affidavit filed in D.C. Superior Court by Audrey Rowe, commissioner of Social Services. These plans include installing modular housing units to accommodate 80 more youths at Oak Hill, hiring more special and adult education teachers and improving drug counseling.

Rowe's affidavit was filed this week in response to documents submitted by the Public Defender Service, which sought a court-ordered change in staffing at Marshall Cottage. In the PDS papers, Marshall Cottage is described as dangerously understaffed and containing "wall-to-wall beds." At one point nearly three weeks ago, the PDS documents said, only one staff member was assigned to supervise 33 boys.

"It is playing with fire to continue housing children in those conditions because it will only take a few disturbed or dangerous boys for a serious outburst to occur in which all the residents will become embroiled," one affidavit read.

Yesterday, instead of going forward with a court hearing, the District agreed to increase to four the number of supervisors assigned to Marshall Cottage during the waking hours.

The effort to increase staffing at the cottage is part of a much larger lawsuit filed by the Public Defender Service, which claims that conditions at Oak Hill and Cedar Knoll violate numerous city codes and federal laws.

Partly as a result of that suit, the city said it would close Cedar Knoll by last October. But the number of youths detained there has increased sixfold since then to about 120, forcing a reopening of a number of dormitories including Marshall Cottage. Administrators attribute the rise in the number of youths in custody to an increase of nearly 200 percent in the number of drug-related juvenile arrests in the past two years.

Administrator Quann said yesterday that with the addition of the modular units at Oak Hill the city now hopes to close Cedar Knoll by the end of June.

"We still need to get out of Cedar Knoll," said Quann. "The physical plant is seriously decayed."