Delaware County was in a similar situation, having finalized its funding list in May, said Linda Hill, director of housing and community development.
"It does require us to reevaluate all of our approved projects," Hill said. "We always knew that the numbers could change at any time. The timing is what was problematic."
She said Delaware County should know within days which projects will be affected.
Chester County was still selecting its grant recipients, so it was less affected by the update. Bucks County's housing director did not respond to requests for comment last week.
HUD's Community Development Block Grants are intended to help low-income residents and improve blighted neighborhoods. To qualify, at least 38.33 percent of the project area must be of low or moderate income (less than $63,050 for a family of four in 2014), according to Montgomery County's housing department.
HUD usually updates those maps every 10 years, based on decennial census data. Beginning July 1, the agency switched to a five-year update based on the Census Bureau's less formal American Community Survey.
In a letter to local agencies, HUD said that transition process required "special tabulation" from the Census Bureau, which delayed the release of the maps.
Montgomery County Commissioner Josh Shapiro said officials were "perplexed why they chose to send those adjustments in the middle of the process."
As a result, for instance, Upper Dublin lost $190,000 for a street improvement project.
And in Springfield Township, a road project lost $33,190 since only half of the intended improvements remained in the eligible area.
There is something of a silver lining to being bumped off the HUD map - it means those communities are on the rebound, with average income rising to moderate levels. But it eliminates a pool of money that many communities have come to rely on for economic-development initiatives and infrastructure upgrades.
Curtis Griffin, superintendent of the Hatboro-Horsham district, said the Community Development Block Grant from HUD would have covered the entire replacement cost for a pedestrian bridge to Pennypack Elementary School that's "beginning to have some structural deficits."
Other fund sources?
"While I was disappointed, it never surprises me anymore," he said. "At the end of the day, there's only so much money that's going to be distributed. You just have to let the process play out."
The district is talking to township officials in hopes of finding other funding sources, Griffin said.
With a half-million dollars returned to its coffers, Montgomery County was able to fund projects that had been rejected or underfunded before.
Lansdale was initially denied funding for improvements to the Third Street corridor; now the borough will receive $200,000. And Pottstown will receive $200,000 to replace 100-year-old underground storm-water culverts throughout the borough.
Lansdale Borough Manager Timothea Kirchner said the street project would have gotten funding eventually, "but not as soon as it is now getting done. It helps us a great deal."