303-233-8383 [email protected]

Project Profile:

Arrowhead Lake Comm. Assoc. Waste Water Treatment Rehabilitation

Project Summary

Arrowhead Sewer Company, Inc. hired Princeton Hydro, LLC to provide engineering services to reinstall an inflow Equalization Tank that floated due to unforeseen groundwater conditions. Given site and layout restrictions, Princeton Hydro designed groundwater and overland flow control elements to buffer the tank from groundwater uplift. The system consisted of two main parts: a diversion channel to direct the overland flow around the tank area, and a subsurface drainage system around the tank. The drainage system consisted of Invisible Structure’s Rainstore3, surrounding the tank with a curtain composed of 94 percent voids, and Draincore2 under the tank, both capturing and conveying water to a 30” outlet pipe. Princeton Hydro also designed an anchor system to fasten the EQ tank to the existing concrete pad.


Lehigh Rd & Orono Drive

Install Size

285 m2 (3000 sq ft) Draincore2 and 1526 units of Rainstore3


Princeton Hydro, LLC


Hartman Contracting and Arrowhead Lake Comm. Assoc.

Project Gallery

A complex problem at the Arrowhead Lake water treatment facility was solved through installing a two pronged solution using Draincore2 and Rainstore3.
Rainstore3 cells are placed in the excavated area. Princeton Hydro, LLC used varying heights of cells - see image schematic below.
Storm water storage and drainage layer were installed at the Arrowhead Lake water treatment facility solving storage and drainage problems using Draincore2 and Rainstore3.
The cover material being placed on the Rainstore3 units.
A schematic showing the varying heights of the Rainstore3 cells and how they were stacked. Drainage starts from the high end, via Draincore2 and Rainstore3, and goes to the low end, via Rainstore3, and finally out though pipe (see photo 7).
The Draincore2 rolls ready for installation.
The Draincore2 is wrapped in geotextile filter fabric.
Crews lower the EQ tank into position over the Draincore2 and Rainstore3.
The outflow pipe shows the system is working (Sept 2003).