This is in Carlsbad where you can dump but does not have potable water.https://www.campendium.com/carlsbad-wastewater-station Someone mentioned there is a Pilot station that has potable water.

RV park at White’s City let’s you dump and fill if a site is open. $15-$20

White City will be the closest. Not sure what the charge would be. We camped there for one night to dump and fill. Carlsbad has a Pilot/Flying J. But, when we were there, the outside faucet was broken and we couldn’t even get fresh water.

For fresh water, we just filled our 6 gallon jugs at White City, from a kiosk, I think it was $1.25 per jug. That's the closest for any water, I know of no "hose friendly" place to fill. But we really enjoyed our stay. We liked Chosa for it's central location to the Caverns