Where are you starting from? There is an outdoor cafe at the 70th St fishing pier, and if memory serves me there is a water fountain on the bike path right behind it. Don't know if it is operational or not. There are bathrooms around 74th St, and a fountain near the children s playground there. In the summer there are often vendors near the parking lots at 158th St. If you take River Road to Alpine there is a Snack Bar open in the summer at the Englewood Boat Basin. You can dine with your bicycle right at one of the picnic tables on the river. If taking Hudson Terrace to 9W, you can make a right into Allison Park, maybe a mile north of the bridge where you can find bathrooms and water. For long rides in hot and humid weather I like to carry an hydration pack along with 2 water bottles filled with an electrolyte replenishment drink.