A dog waits April 19, 2022, for adoption at the San Marcos Regional Animal Shelter. As the human population along the I-35 corridor between Austin and San Antonio continues to boom, shelters are struggling to deal with overcrowding of unwanted pets.

SAN MARCOS — Sad-eyed dogs rest quietly in crates stacked one atop the other before the front desk in the animal shelter’s adoption wing.

There’s Vivian, a one-eyed, German Shepherd mix with heartworms who curls up in the back of her crate and watches people pass by. Her crate neighbor — an 8-pound, black dog with no name — sits as close to the door of the crate as she can without spilling out of the slats.

The dogs are in the lobby of the San Marcos Regional Animal Shelter because there’s simply no space for them in the kennel wings. On this particular Tuesday in April, the shelter has 132 dogs in its facility, which houses only 93 kennels, and 74 cats in its cat room, some of them doubling or tripling up in their crates.

The shelter is bursting at the seams, thanks in large part to spring breeding season and a lack of spaying and neutering of the animals roaming free in Hays County.

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But shelter overcrowding is nothing new in Hays County nor in the Hill Country at large. From San Antonio to Austin, explosive population growth along the I-35 corridor has meant that many animal shelters built decades ago — when communities were much smaller — are overflowing with unwanted animals.

It’s putting the few animal advocates who work to save them under enormous pressure.

“The current animal shelter that we have is just not sustainable with the rise in the human population,” said Christie Banduch, animal services manager for the city of San Marcos. “It’s not sustainable in the long term without expanding.”

In San Marcos, the shelter on River Road is the only open-intake animal shelter for all of Hays County. Smaller, private shelters and animal rescue groups exist in places like Buda and Kyle, but the 93-kennel San Marcos shelter is the only taxpayer-funded facility that is required to take in any and all dogs, cats and other critters from anywhere in the county.

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Some county officials and animal advocates are teaming up to change that. In October, Hays County commissioners approved funding a feasibility study for proposals and planning of a centralized, no-kill animal shelter that would relieve some of the pressure on the San Marcos facility. Next week, a group from animal advocacy organization Team Shelter USA and Animal Arts, which designs shelters, will come to Hays County to conduct that feasibility study, as well as a field operations assessment, to determine how to proceed.

“Hays County needs its own animal services division for the growing population,” said Sharri Boyett, the county’s officially appointed animal advocate. Also, the new shelter would need to be located in a more central part of the county, she said, because “pets who are lost are often not reclaimed because people don’t know their pets were taken all across this county.”

San Marcos isn’t alone: Other fast-growing Hill Country communities are grappling with shelter overcrowding as well.

In Kerr County, voters will go to the polls in late November to vote on a bond that, if approved, will fund a new animal control facility. The new shelter would replace the existing facility in Kerrville, which is the only open-intake shelter for the entire county.

The existing Kerr County shelter is “woefully inadequate,” said Karen Guerriero, president of Kerrville Pets Alive. Her nonprofit formed to assist the animal control facility.

“Our county is growing like crazy, and that shelter is not able to really keep up with the influx of people,” she said.

Shelters in Comal, Guadalupe, Llano and Burnet counties also are feeling the squeeze of surging animal intakes, and discussions are underway on how to best meet the challenge.

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Still, even with promising initiatives on the horizon, the day in, day out struggles of taking care of the community’s unwanted animals takes a toll on people like Banduch. She said she sounds like a “broken record” most of the time when she tells people the importance of getting their pet fixed and treating it as a lifelong commitment.

In early March, the shelter had to take in 36 semi-feral dogs that were being hoarded, and they took over one of the facility’s three rescue buildings. Some were sent to rescue groups, but many had to be euthanized since they had serious medical or behavioral problems and little hope for rehabilitation.

“We have to consider those dogs’ mental health and suffering as well,” Banduch said. “That was a tough one.”

A cat reaches April 19, 2022, through a kennel door at the San Marcos Regional Animal Shelter. As the human population along the I-35 corridor between Austin and San Antonio continues to boom, shelters are struggling to deal with overcrowding of unwanted pets.

A volunteer walks a dog April 19, 2022, at the San Marcos Regional Animal Shelter in San Marcos as other dogs in kennels watch. As the human population along the I-35 corridor between Austin and San Antonio continues to boom, shelters are struggling to deal with overcrowding of unwanted pets.

Christie Banduch, animal services manager at the San Marcos Regional Animal Shelter, looks April 19, 2022, at intake data for the shelter. As the population along the I-35 corridor between Austin and San Antonio continues to boom, shelters are struggling to deal with overcrowding.

Dogs wait April 19, 2022, for adoption at the San Marcos Regional Animal Shelter. As the human population along the I-35 corridor between Austin and San Antonio continues to boom, shelters are struggling to deal with overcrowding of unwanted pets.

Christie Banduch, animal services manager at the San Marcos Regional Animal Shelter, answers a reporter’s questions April 19, 2022, in the cat room at the shelter. As the population along the I-35 corridor between Austin and San Antonio continues to boom, shelters are struggling to deal with overcrowding.

Banduch has a tattoo of a paw print on her left wrist with the words “Embrace The Suck” over it, to remind her to keep her chin up even when things seem hopeless. That’s most days. Lately for every dog that leaves the shelter for a happy home, three more come in needing a kennel.

It’s a constant slog, she said. She has to remind herself constantly that nobody else would care for the animals if she and other rescue workers didn’t.

“These guys need somewhere to go,” she said. “If not us, then who?”

Annie Blanks writes for the Express-News through Report for America, a national service program that places journalists in local newsrooms. ReportforAmerica.org. annie.blanks@express-news.net.

Annie Blanks covers the city of San Marcos for the San Antonio Express-News. She previously covered local government in the Florida Panhandle for USA TODAY and originally hails from Macon, Georgia.