I own a landscape installation company in colorado. The landscapes in Colorado are different from where you're at but this is a common problem that has a singular solution where I am. We put down a 20 year fabric weed barrier then we install 1&1/2" rock over it. The rock slows down the water and the flow of water is now happening above the ground on the weed barrier. I've attached a picture of a completed landscape that we did for your reference.
