Cretex Specialty Products was established in 1983 to provide ancillary products to the sewer construction industry. The company s most notable products are the internal and external manhole chimney seals, which are designed to reduce surcharging/bypassing and lower pumping and treatment costs in a sanitary sewer system. In storm sewer systems, chimney seals provide protection from infiltration of surrounding soil, which can undermine pavements. Located in Waukesha, Wis., Cretex Specialty Products operates within Cretex Companies construction products division. Cretex Companies main source of revenue is the manufacture and distribution of concrete drainage products.