A six-lane highway lined with strip malls cuts through a patchwork of tamed lawns and suburban houses in Delran, where population has sprouted rapidly in recent decades.

The township, which has close to 17,000 residents in about 6,000 housing units, is nearly built out with “less than half a dozen properties” available for multiple new housing units, according to Gary Catrambone, the township council president.

Actually, Delran needs to accommodate more than 700 residences for low- and middle-income New Jerseyans, contends the Fair Share Housing Center, which has sued the township, alleging it is undermining its own ability to fulfill affordable-housing requirements stemming from a series of lawsuits that grew out of the availability of such housing in Mount Laurel.

The dispute has been tense in Delran, with one resident complaining at a public meeting, “Next thing you know they’re going to say, ‘Hey … get out of your house, we got a poor person that wants your house.’ ”

It is a variation of a debate that has played out in hundreds of towns across the state over the Mount Laurel requirements, the subject of decades of New Jersey court cases that required communities to accommodate housing that lower- and middle-income households could afford.

“I don’t think anyone would describe affordable-housing policy in the state in the last 10 years as reasonable or rational,” said Mike Cerra, assistant executive director of the New Jersey State League of Municipalities.

After years without enforcement of those requirements — stalling development of new housing — the New Jersey Supreme Court in a sweeping decision in January ruled that towns had to retroactively act on 16 years of accrued housing needs.

But the court’s ruling didn’t define exactly how many homes each community owed, spurring town-by-town negotiations — and in some cases battles — in communities such as Delran, among the more than 150 municipalities that have not yet settled for varying reasons.

In a town where the median income is $90,500, the prospect of hundreds of new housing units for lower-income residents generates fears that include new burdens on schools and increased taxes. Some critics are blunt.

“If you’re a lazy SOB and you don’t want to work, you don’t deserve squat, period,” Bob Gilbert, a Delran resident, told the township council at an August meeting. “Rent, or go find a cave to live in, or … some third world country to go into.”

Housing advocates say the fight in Delran demonstrates the need for the precedent-setting rulings that began when New Jersey’s high court declared the township of Mount Laurel‘s zoning practices unconstitutional in 1975.

“There are hundreds of municipalities in New Jersey that if they could have done nothing to help lower-income households, probably would have done nothing,” said Kevin Walsh, executive director of the Fair Share Housing Center, the Cherry Hill-based nonprofit that pushes municipalities to accommodate affordable housing.

The Mount Laurel decisions have spurred development of 80,000 homes for lower- and middle-income residents across the state, Walsh said, “and there’s a lot of homes that are going to be built over the next decade because of these settlements.”

But Delran’s case also illustrates the complications: It says at most it could squeeze 285 such units in available spaces; just last year, it put the number at 44, and Fair Share says it actually owes 704.

For years, suburban communities were allowed to pay other towns to build qualifying residences for them. Delran, for instance, paid $860,000 to neighboring Burlington City, which pledged to shoulder some of its affordable-housing burden by adding 43 low-income rental units there.

“Ultimately, towns want to meet these obligations and move on,” Cerra said.

At the Delran meeting, officials spelled out the township’s income qualifications, which are based on Burlington County’s average income of $83,000 and “are likely a little higher than you might have expected,” Catrambone told residents. A family of four making $66,550 or less would qualify for housing designated for moderate-income residents; a family of four earning $41,600 or less would qualify as low-income.

To rent or buy income-restricted housing, residents must be certified by the state. Prices are also restricted; affordable units currently listed for sale in Delran range from $72,000 to $124,000. The average home cost in Delran is about $240,000.

Municipalities can meet the Mount Laurel obligations by requiring that developments include affordable housing. The costs of building those units — which often constitute 20 percent of the development — are subsidized by the market-rate housing. Other options include redeveloping existing housing stock, or seeking tax credits for a fully affordable development.

Delran officials say the township has a surplus of unoccupied affordable housing and is unable to find buyers for a number of units. “Clearly, we’ve had an issue with getting people into these units,” Jeffrey Hatcher, the township’s business administrator, said in an interview.

Walsh said affordable properties in Delran likely “would be scooped up quickly” if they were for rent, rather than for sale. “I’m not aware of any other towns that have this issue,” he said.

Catrambone said the township has exceeded its obligations under Mount Laurel, meeting the state’s requirements in the 1980s and 1990s. Most of its affordable housing — 150 for-sale units — is interspersed in two developments in town; the township also has several group homes.

“At the last measure, we were ahead of the game,” Catrambone said in an interview last week.

But the affordable-housing rules that set the requirements for Delran and other municipalities expired in 1999. The New Jersey Council on Affordable Housing, tasked with developing new rules, failed to do so, leading to litigation that lasted years as advocates challenged — and courts invalidated — updated versions.

The agency’s failures led the New Jersey Supreme Court in 2015 to transfer the responsibility to trial courts. Then, in January, it ruled that towns continued to accrue housing obligations from 1999 to 2015. The housing plans now being hashed out in courts and through settlements with Fair Share and developers must cover that period, along with the years through 2025.

About 150 towns have settled, according to Fair Share, committing to build 50,000 units. Others are awaiting a ruling in Mercer County, where a trial considered conflicting calculations of municipal housing obligations from Fair Share and the towns.

Delran contends its issue isn’t affordable housing, but that vacant land is lacking, generally. “It’s about housing, in general,” Catrambone said. “How much room do we have left to build?”

But Fair Share says Delran is trying to skirt its obligations. It has sued to stop developments that received township approvals  that wouldn’t include affordable housing. Among other arguments, the township counters that Fair Share’s action is too late.

“It doesn’t really seem like an accurate statement that they’re concerned about housing, given that they just approved housing,” Walsh said. While Delran had met earlier obligations, in the intervening years, “they’ve done virtually nothing,” Walsh said.

Catrambone said he couldn’t comment on the litigation. He said the township will comply with the court’s decision on how much housing it owes.

“There’s a number. We don’t know what it is, the court doesn’t know what it is, the people suing us don’t know what it is,” he said. “None of it counts until the court says this is the number. At that point, we’ll meet it.”