(a) In this section, "recreational vehicle park" has the meaning assigned by Section 13.087.
(b) A retail public utility, other than a municipally owned utility described by Section 13.087, providing water or sewer service to a recreational vehicle park:
(1) shall ensure that billing for the service is based on actual water usage recorded by the retail public utility; and
(2) may not impose a surcharge based on the number of recreational vehicle or cabin sites in the recreational vehicle park.