It is a regional hub for taking in stray dogs and cats, but the Chester County SPCA shelter has become a "kill factory," say SPCA volunteers, a former board member, and ex-staff members.

They blame ineffective board leadership, unfilled senior management positions, and a clash of ideologies for a significant rise in euthanasia numbers.

Though shelter management does not dispute that euthanasia numbers are rising, it says it is battling the realities of dealing with a tremendous volume of unwanted dogs and cats, many of whom are not adoptable.

The shelter takes in about 5,000 animals a year, according to board president Conrad Muhly, who said the critics are not representative of those who have worked and volunteered at the shelter.

In April 2012, the nonprofit shelter, was founded in 1929, undertook an extensive renovation to its kennels, which included adding 2,000 square feet of additional space for dog runs, cat housing, and office space.

"I am thrilled with the people that work there. The staff does an excellent job," Muhly said.

"Volunteers and staff are like oil and water in a lot of nonprofits," he said.

The center has about 200 volunteers, 30 to 40 of whom work weekly, spokesman Rich Britton said.

"Volunteers are dropping left and right," said Cathlene Wagner, a current volunteer.

More than a dozen volunteers have formed a group to push for a change in leadership and more effective programming. They are troubled when dogs are euthanized for what they see as easily corrected behavioral issues or treatable medical problems.

"The current management team is not following the mission statement," said Carin T. Ford, a former board member who left the organization in May. "The board is not addressing the issue."

The facility is an open-access shelter, which euthanizes animals considered dangerous or very sick, and healthy animals that have not been adopted when the shelter lacks space.

The shelter takes in stray animals brought in from the county's municipalities, and it also has a five-year, $30,000-a-month contract with Delaware County to accept strays from 46 of its municipalities.

The bulk of the shelter's funding comes from donations and events such as the Forget-Me-Not Gala.

The county's is one of about 3,500 shelters nationwide caring for six to eight million stray cats and dogs annually, only half of which are adopted.

An additional 2.7 million are euthanized annually, according to the Humane Society of the United States.

"I try not to focus on the [Chester County shelter's] euthanasia numbers, even though it is a driver in the industry," Muhly said. "Euthanasia is an ugly thing. No one wants to deal with it."

The shelter will not share its euthanasia numbers but acknowledges they are climbing.

"I was criticized for wanting to save every animal," said Michele Amendola, a former operations manager who recently left the shelter. "I don't understand why that is a bad thing. If we could save every animal, why not try?"

Pennsylvania law does not address cats. Municipalities are under no obligation to care for stray cats. In the region, cats far outnumber dogs at shelters.

"Cats have no shot at life," said Leslie Celia, a former shelter volunteer.

Volunteers say some cats are taken from the intake counter directly to the euthanasia room.

A program to place adoptable cats through pet stores was recently shut down, Wagner said. "The front-office staff said it was too much of a hassle."

Rescues and foster programs have become the lifeblood of shelters, but some are not working with the Chester County facility.

The Pennsylvania SPCA has not pulled animals from the shelter in months, critics said. One rescue group, All Things Pawssible, was told it no longer was welcome to take dogs for adoption, according to Debbie Reilly, a coordinator with the rescue.

Grace Keffer, the shelter's office coordinator, said it was working with a number of rescues and had about 100 foster families.

At the same time euthanasia numbers are on the rise, the shelter has pulled dogs from out-of-state kennels as part of a trial program to bring in puppies for adoption.

It received an unsatisfactory grade in a state kennel inspection May 17 because its records indicated the out-of-state animals did not have required health certificates.

In the same inspection, the SPCA received unsatisfactory marks for housekeeping and maintenance. Some of the issues were chewed dog doors and dog-bed legs, inadequate pest control, and unsanitary kennel conditions.

"These are good people with good hearts working very hard to do everything to help animals," Britton said.

"It is a great organization with tons of potential, but they are not reaching their potential," said Mike Dempsey, a former interim operations manager at the shelter.

He said he was asked to sign a confidentiality agreement when he left.

Contact Mari A. Schaefer at 610-313-8111, mschaefer@phillynews.com, or follow @MariSchaefer on Twitter.