In the same week that Mayor Bill de Blasio announced a plan to open 90 new homeless shelters in New York City over the next five years, City Council legislation could limit his ability to do so, according to advocates for the homeless.

The bill would prohibit the placement of emergency and permanent homeless shelters in neighborhoods with the highest concentration of these facilities, unless both the Council and City Planning Commission agree there's an overriding need.

This, advocates argue, could embolden a NIMBY attitude and is legally dubious, as it could conflict with New York City's right to shelter law—particularly in emergency situations. A seminal interpretation of the New York State Constitution currently mandates shelter services for anyone in need within NYC.

"When we have a sudden increase in demand for shelter, the city needs to open up capacity," said Coalition for the Homeless policy director Shelly Nortz. "And I've been on the phone with the city last-minute too many weeks this year when we were running out of shelter and they had to open them immediately."

New York City's homeless population hit a new record last fall, exceeding 60,000 children and adults.

In pitching his homelessness plan, Mayor de Blasio predicted that his approach would not be "politically popular." In an effort to keep homeless families close to their communities—schools, churches, friends—new shelters will be distributed according to the number of people entering shelters in each neighborhood.

A new map from Crain's shows neighborhoods with high rates of new shelter entrants, covering a significant number of low-income communities of color.

People are entering the shelter system at the highest rates in central Brooklyn and the central Bronx, as well as the south Bronx and Harlem, according to Crain's. A City Council report this week shows some overlap between these neighborhoods, and those with the highest concentration of shelter beds: the central and south Bronx, Chelsea, Midtown, East Harlem, and Brownsville.

Councilmember Brad Lander, who's sponsoring the City Council legislation—part of a larger package of bills intended to fairly distribute all city services city-wide—said his legislation will bar the city from over-saturating low-income neighborhoods of color with shelters, while still supporting the mayor's vision of opening more shelters in neighborhoods that have very few.

According to City Hall, seven community districts in NYC currently have no shelters at all, like Manhattan CB 1, which covers lower Manhattan south of Canal Street, and CB 11 in Brooklyn, which covers Bay Ridge and Dyker Heights. From 1999 to 2015, according to the City Council, the five community districts that have seen the largest shelter expansion are communities of color, in the central Bronx and central and eastern Brooklyn.

"For decades we've done a lousy job of two different things," Lander told Gothamist. "First, enabling families to keep kids in their school if they enter the shelter system. We've also done a lousy job of distributing our shelters fairly."

"You can imagine circumstances where [these priorities] come into conflict, and many more situations where they don't," he added.

Lander also challenged the notion that his legislation would run afoul of right to shelter. Under his bill, the top ten percent of community districts for shelter concentration—five in total—would be exempt from consideration for new shelter sitings. "Ninety percent of the city would be just as available as it is today," he said.

Another bill in Lander's package would require the city to publish maps online, showing how shelters and other city services are currently distributed.

"People who are engaged in NIMBY organizing often say their neighborhood already has its fair share," he said. "Part of the problem right now is, it's hard to see what the truth is."

Maspeth, Queens vehemently protested a shelter in their neighborhood last summer; according to the city, there were no shelters in their community district when the plan was announced. Lander would see communities like this one open more facilities.

"The fact that he's missing is that it's incredibly difficult for the city to open a shelter," countered Josh Goldfein, a staff attorney with the Legal Aid Society's Homeless Rights Project. "It's not like they're just moving monopoly pieces around on a board. In the last two years the city has been frantically scrambling to open as many places as they can."

While the city is currently not legally obligated to alert constituents about a new shelter opening in their neighborhood, the mayor's new homelessness plan calls for 30 day notice for all permanent shelters, with the opportunity for at least one community meeting. It also calls for as short as same-day notice for emergency hotel placements, like when homeless are moved into commercial hotel rooms.

The City Council report argues that Lander's approach, which requires more transparency, would actually go far to curb NIMBYism. Emergency shelter citing, which does not require community notification, "reduces confidence in the City's processes and may in fact exacerbate NIMBY sentiments," it states.

From Maspeth to Crown Heights, community members have accused the city of failing to give enough notice (even when the announcement comes through a month in advance). This weekend, Crown Heights residents packed a meeting about a proposed shelter on Bergen Street, demanding more transparency. The standing-room crowd cheered when Assemblywoman Diana Richardson took to the mic, insisting that the city "shut down" the project altogether.

They also argued that their neighborhood is oversaturated, with 19 nearby shelters (according to the city, there are 10 traditional shelters in districts 8 and 9, which cover Crown Heights, and 16 in neighboring district 3, which covers Bed-Stuy). Residents accused the city of "dumping" shelters on their streets. Crown Heights is not in the top 10 percent of saturated districts according to Lander's guidelines.

Advocates stressed that they do not believe new shelters are the solution to addressing New York City's homelessness crisis.

"The way to solve this is with more permanent affordable housing," said Goldfein. "The city could... increase the number of affordable apartments in their affordable housing plan."

Between a new right to counsel policy for tenants facing eviction and momentum behind a state bill that would bridge the gap between rental assistance and market rents, "We are finally looking at some tools to turn the population around," he added.

Still, curbing shelter expansion under the current circumstances is "not an option" under current homelessness levels and will "provide the NIMBY crowd with tools that they can use."

Mayoral spokeswoman Jaclyn Rothenberg said the city is "still reviewing" Lander's legislation.