A TEXAN transplanted to D.C. once confided that for her the essence of life in Washington lies in the words "Let's have lunch."

No doubt about it, in the District, business as usual is lunch, and how to enjoy it is a distinct form of prideful connoisseurship. Those who partake regularly have refined the ritual and elevated it to the art form it is today.

But daily decisions about what to do for lunch can tax the creativity of even the most sophisticated worker. Planning for lunch can consume an extraordinary amount of energy.

If you yen for a tranquil noon-hour (or so) hideaway, where you won't have to stand in line, elbow tourists, make reservations or order drinks, here is a thoroughly researched list of some not-so-crowded sightseeing spots and places for small picnics. They are located conveniently near the bastions of Federal dronedom: the Federal Triangle, L'Enfant Plaza and Capitol Hill. (Apologies to those who work in Georgetown and Connecticut and K. There are enough lunchtime diversions there for three careers.)

You probably can walk to most of these places, which is better for you than three martinis, anyway. And what prospective program manager or contractor wouldn't become a little more pliable with an elegant picnic, even if it is in a bag?

Ten "alternative" lunches:

Titanic Memorial--Gertrude Vanderbilt Whitney sculpted a strikingly serene and touching monument to commemorate the male passengers of the doomed oceanliner Titanic, who gave their lives so that women and children could live. The draped granite figure with outstretched arms looks out across the water with a gaze of infinite reach. A stone bench, designed by Henry Bacon, architect of the Lincoln Memorial, surrounds the statue. Benches are also available throughout Washington Channel Park. The statue is in Washington Channel Park, Fourth and P streets SW, next to Fort McNair and across the channel from East Potomac Park.

Fountain No. 4--The name doesn't exactly conjure up the image of a Trevi Fountain in Rome, but Fountain No. 4 is a charming jet d'eau surrounded in spring by beds of blue, yellow, white and purple pansies. Through the summer there will be begonias, marigolds, cana, vinsa and scarlet sage. The garden is visually secluded, pretty and worth a visit, but because it is in the shadow of Route I-395 and National Airport's flight path, it can be a bit noisy. If so, just sashay with your sandwich over to the nearby Tidal Basin. Located behind the Jefferson Memorial where East Basin Drive and Ohio Drive join and the Tidal Basin flows into the Potomac.

Tidal Basin Boat House--Ply the same waters as Fanne Foxe in a pedal boat rented by the hour. The boat-rental facility is open from 8 a.m. to 9:30 p.m. and charges $3.35 per hour. You must be 16 or over to rent a boat, which holds two people. Pedal boats are available on a first-come, first-served basis. The rental season is from April 1 to the end of September. For further information: 484-3475. Located near the intersection of 15th Street and Maine Avenue SW, across from the Jefferson Memorial.

Washington Boat Lines Shuttle Cruise--Take a slow boat to Georgetown on The Spirit of '76. The two-hour ride costs $6.50 per person; groups of 25 or more, $6 per person. The boat leaves Pier 4 at 9 a.m., 11:30 a.m., 2 p.m., and 8 p.m. every day except Monday. Snack bar on board. First-come, first-served basis from March 26 through July 3. From July 5 through mid-October, Washington Boat Lines will also offer a buffet luncheon afloat. The one-hour lunch cruise will depart at 11:30 a.m. and 1 p.m. Monday through Friday. Reservations recommended. Luncheons in the $8 range not counting drinks and tips. Pier 4 is located at Sixth and Water Streets SW, near the Gangplank Marina and Restaurant. 554-8000.

L'Enfant Plaza Hotel Swimming Pool--Membership in the L'Enfant Plaza Hotel's rooftop swimming pool entitles you to all the swimming you can manage from Memorial Day through Labor Day. Hours are 10:30 a.m. to 8 p.m. seven days a week. Annual membership rates: $275 for individuals and $325 for families. One guest admitted free. A snack bar serves light luncheon fare on the patio. L'Enfant Plaza Hotel, 480 L'Enfant Plaza East SW.

D.C.War Memorial--The names of 26,000 Washingtonians are inscribed on this unpretentious memorial to the residents who served in the armed forces during World War I. The open-air rotunda enclosed by marble columns is surrounded by a quiet, shaded park. Bring a blanket; no benches available. Walk to the midpoint of the Reflecting Pool (facing the Lincoln Memorial) and turn left. D.C. War Memorial is about 100 yards to the left of the Reflecting Pool.

Independence Garden--Get back to the land on Independence Avenue. Not to be confused with an exhibit or beautification program, this is a teaching garden demonstrating how small urban spaces can be used to produce wholesome food and beautify the community. There are small gardens in waist-high platforms suitable for wheelchair gardeners, a 625-square-foot plot typical of a backyard garden and a working 3,000-square-foot vegetable garden, which actually feeds the volunteer gardener's family of seven. Coordinated by Garden Resources Of Washington (GROW) with the cooperation of Metropolitan Master Gardeners. The site is suitable for sightseeing, but picnic space is not available. Once your appetite is whetted with the fresh veggies, pick a shady spot on the Mall. Independence Avenue and Sixth Street SW across the street from the Air and Space Museum. For further information, call GROW at 797-9284.

The Botanic Gardens--It is hard to believe that the Bartholdi Fountain in the Botanic Gardens once caused a Victorian sensation. During the late 19th century the 12 lamps around the rim of the fountain's basin were among the earliest public displays in Washington of the new-fangled electric lights. Designed by Fre'de'ric Auguste Bartholdi, who is better known for the Statue of Liberty, the fountain is the centerpiece of a visually formidable garden. Tended by a single (and surely outstanding) employe of the U.S. Botanic Gardens, it is in bloom brilliantly from early spring until the first frost. Benches available, shaded by chestnut trees. Located on Independence Avenue and First Street SW, across the street from the U.S. Botanic Gardens Conservatory.

John Marshall Park--Workers were busy all winter so that Washington's newest park could be dedicated May 10, 1983. It is named after the 19th-century U.S. Chief Justice John Marshall, who once lived nearby in a long-since vanished rooming house. Residing there now are two bronze figures, eternally engaged in a game of chess, by Lloyd Lillie, a replica of John Marshall's sundial and assorted bronze dragonflies, turtles and frogs in the fountains. Benches and a few tables available. Located on Pennsyvlania Avenue and Fourth Street NW, across the street from the National Gallery of Art East Building.

The Floral Library--Put this on your list for spring or fall. The tulips in the National Park Service's Floral Library are well worth a stroll. The fleeting riot of April color is followed by a display of annuals in mid-September. The garden is dormant in summer. Brochures identifying the flowers are available in the garden. Because the site is more suited to sightseeing than picnicking, check out the flowers and then walk across the street to a park near the Tidal Basin between the Washington Monument and the Jefferson Memorial.