Bolsa Chica Wetlands


It’s been a century since the Bolsa Chica Wetlands were truly a “wetlands” - connected to the Pacific Ocean via seven concrete box culvert and weir units that control tidal flow from a renewed 397-acre full tidal basin. The muted basin is the nesting place of several threatened species of wildlife. For 100 years, the basin has been a

relatively dry, below sea level oilfield. A huge engineering project developed to smoothly control the tidal flow, completely phasing out oilproduction over several years.


Large gates at each end of the 150’-plus long culverts control the flow and containment of water; it is critical that ocean water not flow into the adjoining ground, nor oil-contaminated ground water flow in reverse. When originally constructed, the culverts and weirs used soil-tight design joints that did not maintain control over leakage. A
combination of concrete repair, grout injection and a critical geotextile-reinforced, spray-applied polyurea membrane was the solution.Innovative Painting and Waterproofing Inc. performed the repair, grout and polyurea installation.


Deteriorated sealants, grouts, patching materials and backer rods were removed, and after extensive grout injection and concrete repairs, joints and surrounding areas were cleaned and ground to ensure adhesion;keyways were cut on each side of each joint for membrane termination and with 8 oz. Geotextile fabric cut to specific widths, 150 mils of Polycoat’s Series 5502 Aromatic Polyurea was installed as the final membrane and terminated at the keyways.


The culverts are a confined space that required constant air monitoring and specific safety controls. The tight quarters meant uniqueworking conditions, and even with gates in operation, tides dictated the working hours, with a short project completion window as well. Innovative deployed two complete Graco EXP-2 Reactor trailer-mounted
workshops and two full polyurea crews, plus repair and injection staff, to meet the critical deadlines. Periodic 24-hour operations were required to perform parts of the operation and to monitor pumps controlling water flow during high tides. Gates were finally opened, tides flowed, and the choice of polyurea as the membrane system proved to be successful.



Jim Sliff
Vice President

Innovative Painting & Waterproofing Inc.


www.waterproofingcontractor.com