Nearly 30 years after a flood devastated much of downtown Frederick, city officials last week announced that more than 180 properties have been removed from federal flood plain maps.

That means that many of the homes and businesses in downtown Frederick are no longer required to pay flood insurance, which has cost some residents as much as $1,000 a year, said Richard Lind, assistant city engineer.

Much of the area has been protected from massive flooding since the construction in the 1980s of four underground culverts designed to contain Carroll Creek in the event of catastrophic rains.

But businesses and homeowners have been required to continue paying flood insurance because the city's flood-control measures were not up to federal specifications. Continued changes in the network of levees and underground channels designed to protect Frederick from the flooding of Carroll Creek finally met federal approval last year.

In October, Federal Emergency Management Agency officials told city leaders that much of the downtown area could be removed from flood plain maps unless property owners appealed the newly drawn flood plain boundaries.

On Jan. 24, the city received final confirmation that there were no appeals from landowners, and the area has been removed from the flood plain.

"We're tying up loose ends," Mayor Jennifer Dougherty said. "This was the promise of the flood-control plan, and now these residents can take the benefit of it finally."

It has been a long and tangled process to get downtown Frederick off the flood plain map, which designates areas that are likely to be damaged by serious flooding.

Carroll Creek has flooded Frederick many times, but a 1976 flood prompted the city to build a flood-control system. In November 1985, the city began work on four large concrete culverts that channel Carroll Creek underground. The work continued until October 1995, according to city records.

But the city did not check with FEMA officials about what the agency required to change the flood plain map, Lind said, so much of the 1990s were spent bringing the flood-control project up to FEMA requirements.

Complaints from homeowners and businesses starting rolling in.

"The city was in a bad spot, because they had invested all of this money in the project and people were still having to pay flood insurance," Lind said.

The 1976 flood, the worst in city history, came after several days of heavy rain. More than seven inches of rain fell in 16 hours, according to news reports from the time. Winchester Hall, the seat of Frederick County government, was flooded, as were hundreds of other buildings across the city.

Photographs taken at the time show that the city's main intersection, Patrick and Market streets, turned into a small lake, with water reaching near the tops of some stranded cars. Damage estimates were as high as $25 million.

At the time, federal law did not require flood insurance in the area, Lind said. New federal laws in the 1970s and 1980s began requiring insurance for areas, such as much of downtown Frederick, that were deemed vulnerable to floods.

The city applied to FEMA in 1994 to have parts of the city taken off the FEMA's flood plain maps -- 10 years after work had begun on the Carroll Creek flood control project, according to city records.

FEMA asked for more information about the project in 1996, then asked for additional work before they would alter the flood plain maps. The process dragged on through the late 1990s, with the city missing a deadline for submitting information to FEMA, then the agency asking for more information. The process finally began wrapping up last year.

"There was a such a push to get [the Carroll Creek flood-control project] done," Dougherty said of the work in the 1980s, "that sometimes [the city] rushed through, and all for the greater good, but we still have to play by the rules to get the federal designation, so we are glad to get it cleaned up now."