Description: Manhole risers, designed and manufactured by Whirlygig, are derived from a revolutionary method and patented process designed for numerous applications.
THE BEST-IN-CLASS MANHOLE RISER/COLLAR SYSTEM
Whirlygig is a revolutionary method of manhole riser/collar installation. It is size accurate, installed in minutes and leaves no doubt about quality control. Cast-in-place on site, our manhole riser/collar system is ideal for new construction or rehab projects.
Over 200,000 installations across America and growing every year!