Auckland traffic has become so bad the SPCA can't do its job properly, so it's fundraising for a new building.
Chief executive Andrea Midgen says covering the whole Auckland area from the one site in Māngere is "becoming really problematic".
"We're finding fosterers can't travel as far as they used to because it just takes them so long. So we're losing the network that we had to be able to cope with all of the animals."
Ms Midgen says the consequences of that are grim.
"We don't want to be euthanising healthy animals, so we pull all the stops and a lot of the staff have to take home a lot of the animals to help us out.
"But the harsh reality is animals die. Or animals are not seen to in the time when we can help them the best we can. Animals that could be rehomed are not, which is not a great outcome."
Ms Midgen says people aren't desexing their pets when they buy from Trade Me or friends.
"There's a population issue, particularly in the cat arena. It's become a real problem because there's more animals than wanted, really."
The new site in Hobsonville will foster and adopt animals, host a doggy day care and also be the base for inspectors.
"We'll have plenty of animals to be adopted there and as they're reduced we'll just top it up from the Māngere site," Ms Midgen says.
But the SPCA still needs to raise around $2m for the $6m project.
Ms Midgen says they've had generous donors so far and hopes the public will help out further so the SPCA can "crack on and build it". They're also calling on suppliers and builders to give them good rates.
"People love animals and nobody can dispute the issue we have in Auckland with traffic and being able to provide the services we need to for injured, sick and abused animals. We're hoping they'll open their hearts and help us out."
If the money is raised, the SPCA hopes to start earthworks in October.