Roof Drain Cisterns

Hanover, New Hampshire

Roof Drain Cisterns, Dartmouth University – Hanover, NH

The scope of this project consisted of (1) 60,000 gallon cistern assembly for Dartmouth University’s new life science building. The life science building, costing an estimated $94 million, was one of the primary projects of the $1.3 billion raised in the Campaign for the Dartmouth Experience fund raiser. In April Phoenix Precast Products was approached regarding production of (1) 60,000 gallon rain water cistern. Phoenix began designing and produced the following products for the project:

  • (6) 9’ x 16’ x 10’ ID 10,000 gallon holding tanks with holes on both sides
  • (12) 3’ tall, ø30” grade rings

The cisterns were designed as 2 assemblies of 3 separate 10,000 gallon tanks linked together with piping through the holes cored into the sides, to ensure the pieces could be moved into place with ease as well as lower the cost. All pipe connections used airtight boots to ensure a clean seal. All tank pieces were coated in an exterior damp proofing mixture to ensure there is no leakage. After assembly, the grade rings were put in place to allow access after the lot was backfilled.

Key Points:

  • Heaviest piece weight 28,500 Lbs
  • All tanks coated with exterior damp proofing mixture
  • Total concrete: 114 yards
  • All pipe connections booted to be airtight
  • System broken into 2 tank assemblies but maintained specified capacity
  • 2 access points in each tank raised to grade with grade rings

**This project was a great example of how Phoenix Precast Products can use smaller tanks in an assembly to meet a predetermined capacity, while minimizing on site excavation work and cost.