One of the last traces of Washington's old waterfront is about to receive a major facelift.

Maine Avenue's fish markets, for many years a popular spot for purchasing fresh seafood products, are expected to undergo a renovation that will cost about $1.5 million.

Plagued by inadequate parking facilities and outmoded refrigeration and sanitation equipment, the facility will have a new look by late next year.

"The place needs to be brought into the modern times," said Joyce Cappon, acting chief of the commercial branch of the D.C. government's Community Development Department.

The project, which is expected to be funded by a combination of monies provided by the Economic Development Administration and the city government, includes the construction of a small park, improved roads in the vicinity, and additional parking spaces.

Three other District government agencies, the community development unit, the Business and Economic Development Office the Department of Transportation and the Department of General Services are involved in the project's evolution.

For many years, merchants along the market have feared redevelopment, which has changed the face of Southwest over the 15 years.

Now, however, those merchants apparently have become convinced that the redevelopment plans can serve only to promote their business. We're not out to get them," Cappon said.

"We hope to fix up the place as a place to do business," said David Smith of the business development agency. "Many people will benefit if customers have a place to park."

District officals hope the project will be further demonstration of their ability to use EDA funds. The federal agency, which provides money to businesses and communities for business development activities has committed $3 million for fiscal 1980 for District projects.

At the Maine Avenue site, the project includes a waterfront park, which will be similar to nearby parks alongside the neighborhood seafood restaurants. The small parks will be landscraped and will include trees and benches, at a projected cost of about $800,000. Ultimately, the park will be turned over to the National Park Service.

A cul-de-sac will be constructed at a projected cost of about $300,000. That paved area will aid traffic flow at the market. An expanded parking lot and new parking meters will be included.

In addition, city officials hope to develop plans to install modern refrigeration equipment at the markets to improve sanitation at the riverfront site.