Terre Hill Stormwater Systems received a U.S. Patent, # 7,798,747 B1 for a Stormwater Capture Module known as the Terre Arch. The Terre Arch is a precast concrete multi arched structure used for underground infiltration of stormwater. The Terre Arch greatly enhances the ability to infiltrate and remove stormwater from the the runoff thus improving volume reduction and facilitating the issuance of a NPDES permit.
The Terre Arch is a structural infrastructure product. It has a HS-25 load rating without any cover. This means that there is no need to cover the Terre Kleen with any material other than that needed to complete the finished grade. This means that when there are areas of high ground water tables, you may still be able to install a Terre Arch infiltration system as the lack of need for cover enables the placement of the Terre Arch closer to finished grade and thus, allows the engineer to comply with the separation distance from the ground watter elevation without risking grade subsidence.
The Terre Arch is also cost effective. With a properly prepared excavation with a 6 inch stone base, a Terre Arch system can be delivered and installed for approximately $4 per cubic foot. Adding the cost of backfilling and cover, the total installed cost of the Terre Arch system is equal to or less than most other underground infiltration systems, including plastic and HDPE pipe and proprietary systems.
