The District has been allocated $30 million for 17 public works construction projects that may create 1,300 jobs here within the next six months, renovate several historic buildings, improve numerous parks and streets and build a $12 million addition to the city's new but already overcrowded jail.

The Federal funds are part of the $4 billion job-creating public works program approved by Congress, and signed by President Carter last Friday, to spur employment around the nation. Under a similar $2 billion public works program approved by Congress last summer the District is now getting $10 million for seven projects and Prince George's County is getting about $5.5 million. Few other area jurisdictions have had sufficient unemployement to qualify for the grants.

District unemployment averaged 8.6 per cent in March and 9.1 per cent last year, when the city had an average of 75,000 persons unemployed on any one day. Unemployment averaged 4.9 per cent in the Washington metropolitan area during March and 5.2 per cent last year. The nation's unemployment rate averaged 7.3 per cent in March, but has been higher in the construction industry.

The seven District projects funded with the $10 million are under construction already and are providing work for an estimated 500 persons. The exact number employed on the projects will not be tallied until July. The current public works include several park and street construction projects, ernovation of the 100-year-old Eastern Marker, additional work on the National Children's Island near RFK Stadium and modernization of more than 550 public housing units in Anacostia.

The newly funded projects include $5 million to construct streets, curbs, sidewalks and plant trees in more than a dozen sections of Anacostia that have never had paved sidewalks or curbs and where the streets are "just a little blacktop over dirt," according to Terry Peel, capital improvements director of the city's budget office. Of the initial $10 million grant, $1.5 million also is being spent to upgrade old Anacostia streets.

An additional $4 million will be spent to upgrade streets in the 14th Street Northwest urban renewal area, $6 million will go to improve sewers on Capitol Hill, $4 million to build five floors of municpal office space above a new fire house at 6th and F Streets NW, and about $1 million will be spent to help renovate the city's old central library, at 9th Street and New York Avenue NW, for use as a graduate library for Federal City College.

Fort Lincoln, the new town in far Northeast Washington, will get a $1.1 million park and almost $1.5 million will be spent to construct parks in the 14th Street Northwest urban renewal area. Trees and shrubbery will be planted at Judiciary Square, with a $335,000 grant, and Anacostia's Watts Branch Park will receive a $500,000 face lifting.

The first two floors of the District building will receive a $500,000 renovation, the Georgetown Market at 3276 M St. NW will be completely restored with a $700,000 grant and renovation of the Eastern Market, at 225 7th St. SW, will be completed with $275,000. Some $300,000 of the initial $10 million grant is now being spent renovating the market's roof and support columns.

But the largest single grant, $12 million, will go to add two new wings to the year-old D.C. detention center near RFK Stadium, which city officials hope will finally allow them to close the 100-year-old D.C. jail. They had hoped to close the old jail when the 960-cell new facility was opened last spring, but the growing number of inmates has forced the use of the old jail as well.

The public works program, passed by Congress last July after two vetoes by former President Ford, is presently pumping $2 billion into construction projects in an effort to create 300,000 jobs, stimulate the economy and improve public facilities around the country.

President Carter's economic stimulus package proposed an additional $2 billion in public works programs during this fiscal 1978. But Congress voted $4 billion in public works projects this year, with virtually all of the money to be spent by Sept. 30.

The District projects were all in advanced planning stages but none of them were funded in this year's $35 million capital budget. The project grants approved by the Commerce Department's Economic Development Administration will total $40 million, according to Peel.

EDA was swamped last summer with more than 25,000 applications, asking $25 billion in public works projects, the $4 billion will go to fund additional projects from that initial list of applications.