My husband and I will be taking our first trip to CSA in mid-December. My husband doesn't swim but enjoys playing in the surf. Could someone please describe the beach conditions regarding how quickly the water gets deep and if there is any undertow. Are there any lifeguards on duty? We visited a resort on the Riveria Maya last year that had barriers to protect the beach which made a relatively calm shallow area for him to enjoy. Any information you can provide will be greatly appreciated!