TreePeople is a nonprofit organization that addresses urban issues, such as water and energy conservation, flood prevention, and stormwater pollution. The TreePeople Center for Community Forestry is a state-of-the-art environmental education campus in California’s Coldwater Canyon Park.

Designed to achieve a LEED Platinum rating, the center features a 250,000-gallon underground concrete cistern. The largest of its kind in the continental U.S., this tank captures rainwater to irrigate the center’s gardens and forests. The cistern is covered with landscaping, including an elaborate labyrinth. Because access for maintenance and repairs is almost impossible, the owners needed a permanent waterproofing solution for the structure.

Conventional waterproofing membranes deteriorate over time, so the center’s owners opted instead to add Kryton waterproofing admixture to the fresh concrete. When added to the concrete mix, this admixture cures to form crystals that fill the spaces between concrete particles, permanently waterproofing the structure. It also reacts with incoming water to self-seal any small concrete cracks, providing lasting protection against leakage.

View all of the 2011 GreenSite projects at