Represa Billings is the largest reservoir in the metropolitan region of São Paulo, covering 127 km² with a total volume of approximately 1,228.7 million cubic meters. The reservoir has a mean depth of 10 meters and a perimeter of roughly 900 km, giving it an extensive, branching shoreline. It is divided into two compartments separated by a barrier: the larger Pedreira section at 112 km² and the smaller Rio Grande section at 15 km². The reservoir spans multiple municipalities, including Santo André, São Bernardo do Campo, Diadema, Ribeirão Pires, Rio Grande da Serra, and the city of São Paulo itself.

Kayaking is an established activity on the reservoir. The NGO Meninos da Billings runs a paddling program called Remada na Quebrada, offering canoeing and kayaking on the water. Organized boat tours also operate on the reservoir, including routes to Ilha do Bororé, a neighborhood in the Grajaú district on the southern edge of São Paulo. This island is accessible by ferry and offers a notably different pace from the surrounding urban environment.

Access to the reservoir is most practical by car, with Avenida dos Bandeirantes and Rodovia dos Imigrantes serving as major approach routes. Public transportation options are limited and typically require multiple transfers. The reservoir's extensive and irregular shoreline means that access points vary considerably by area, and researching the specific arm or section you plan to paddle is advisable before visiting.

Water quality is a significant consideration. The reservoir has documented issues with wastewater discharge, plastic waste, and the effects of informal settlements along its margins. Fishing is permitted in authorized areas, though some zones carry restrictions related to water quality. The most commonly caught species include trahira, giant trahira, and redbreast tilapia. The average water residence time ranges between 50 and 100 days.

Despite the urban pressures, the reservoir retains areas of natural beauty, with freshwater beaches and surrounding green spaces. Sun protection is particularly important when paddling here, as the open water surface intensifies solar exposure. Recreational vessels operating in Brazilian waters require registration and a Vessel Inscription Title (TIE/TIEM) issued through the Brazilian Navy's Directorate of Ports and Coasts, valid for five years.