PARK MESA — With tens of thousands of Southern California homeowners forced to purchase costly insurance after the drawing of new flood maps by the Federal Emergency Management Administration, more than 600 Park Mesa Heights and Hyde Park homeowners are relieved to not be among them.

But it took much activism on their part.

In 2009, FEMA designated the Park Mesa Heights area as a flood plain for the first time, after the agency learned that railroad tracks along Hyde Park were not meant as a berm against floodwaters.

Upon receiving the notice, residents lodged complaints with local officials, who in turn notified higher authorities of their constituents’ concerns. Chief among them: that the new and expensive — annual premiums can be as high as $1,700 — requirement would be unfair, because the area had never been the site of a significant flood; and that maps drawn in the 1980s had already indicated that the area was not prone to flooding.

“As it turned out, [residents] educated [Los Angeles City Councilman Bernard Parks] about a problem that we didn’t know about,” Rep. Maxine Waters said during a Jan. 14 press conference in front of a home on 54th Street. “FEMA did not tell us that they had redrawn these maps … I think the city of Los Angeles was taken by surprise.”

But “we were able to get [FEMA’s] ear very quickly because we [in Congress] authorize their budget and in order to be on good terms with us they have to listen to what it is we are saying,” she added. “We had no real resistance from FEMA. They quickly said, ‘Let us revisit this.’”

Added Parks: “The tracks are interesting because FEMA viewed them as a berm to stop flooding because they have a slight rise. When they found out after 40 years … that they were not built to be a berm, they eliminated them and projected where the flood would go if the land was all flat — and that’s how they came up with that.”

In response to considerable pressure from residents and the offices of Waters and Parks, FEMA decided to take a second look at its map of the area. Requesting data from Los Angeles County, they found that there were flaws in the flood map, then revised it to exclude Park Mesa Heights. As a result, these homeowners will be entitled to a full reimbursement that they can expect to receive within two years.

Isaac Robinson, who hosted the press conference at his home and led the charge for the Park Mesa Heights area, became aware that his area was deemed a high-flood risk area after receiving a letter from FEMA last year. The federal government informed property owners in more than 150 cities and unincorporated areas in Los Angeles, Orange County, Ventura, Riverside and San Bernardino counties about the new requirement. Most of these homeowners live near creeks and rivers, below dams or in low-lying areas that are at a greater risk of flooding.

“I finally got FEMA’s flood maps, and when I looked at it, they have a flood zone that comes across my street that was totally out of whack with reality,” he said. “Am I to believe that water is going to cross the street and flood without draining out at the corner? … There is an out-fall sewer at the corner of 59th Street, and this sewer is built to drain water to the ocean. This street is designed to take water to the out-fall sewer.

“I don’t think the city has any homes that are built that low to the ground because there is an ordinance that your foundation has to be six inches before you start building the wood,” he added. “Then you have the curb, the sidewalk and a raised lawn that equal at least one foot. How is the storm going to destroy somebody’s home here? It may splash around a bit.”

In the controversial projections, FEMA estimated that the area was prone to a one-foot depth of water. After Monday’s thunderstorm, the Wave revisited the area on Tuesday to determine whether it had experienced any flooding. Water did not appear to have surpassed the curb, and was steadily draining out at a nearby storm drain.

According to Parks, FEMA hired a consultant to draw the maps, but never assessed the area for flood risks by walking through the neighborhoods and taking measurements.

“They did a projection, they didn’t do any study, they did it merely on what they perceived,” said Parks. “They have identified flood zones in a higher elevation and a non-flood zone in a lower elevation. We began to realize that their projections and their maps were done in error… They basically superimposed new technology on an old map. They did not do a physical study or an observation study because they didn’t have the money. So, they just ignored it.”

The area — shaped like a half-circle — is bounded by Hyde Park Boulevard to the south, 5th Avenue to the west, West Slauson Avenue to the north and Arlington Avenue to the east.

“They made a mistake here, this is not one of those areas that needed to have flood maps done in such a way that would cause people for flood insurance that they don’t need,” said Waters. “Let’s be clear, flood insurance is necessary for millions of Americans. Accurate flood maps are critical for ensuring that those Americans who need flood insurance pay actuarially sound rates. When the maps are wrong, FEMA has a responsibility to take action so that homeowners aren’t saddled with an unnecessary expense.”

Still, the victory may be short lived; according to Parks, further investigation could expand the maps. A community meeting will be scheduled in the coming months, where FEMA officials will discuss how the flood maps will work and how reimbursements will be distributed.

“We have come quite a ways because we have been taken off,” said Robinson. “But we still have a long ways to go.”