HydroCAD Supports
Stormwater Storage Products from
Terre Hill Stormwater Systems
HydroCAD provides full support for the stormwater storage products offered by Terre Hill Stormwater Systems, including Terre Arch™ and Terre Box™ stormwater chambers.
This partnership allows Terre Hill products to be easily used within any HydroCAD model for stormwater storage, detention, or infiltration. HydroCAD includes complete Terre Hill chamber definitions, plus an interactive chamber wizard for easy layout, pricing, and modeling of underground storage systems.
Support for Terre Hill products was added in HydroCAD 9.0 build 8. If you have an earlier version of HydroCAD, you must obtain a program update in order to model Terre Hill chambers.
How storage is modeled
Stormwater
storage typically appears in a HydroCAD model as part of the
storage definition for a "pond". In the simplest case, HydroCAD
calculates the total available storage, including the interior of the chambers,
plus the void space in any surrounding stone.
For a more complete analysis, a full stage-storage curve is calculated so that
an inflow or runoff hydrograph can be routed through the pond. The resulting analysis indicates the water
levels attained throughout the rainfall event, as well as any discharge
that may occur through outlet devices or infiltration into the surrounding
ground.
Flexible storage options
Each HydroCAD pond may include an unlimited number of storage definitions as required
to describe its overall storage characteristics. This makes it
easy to model complex storage arrangements, such as a combination of multiple
chambers, pipe storage, catch basins, or other contributing volumes.
But the most significant feature is the ability to embed (bury) chambers in a bed of stone, and have HydroCAD automatically calculate the combined storage at any water surface elevation. This makes it easy to determine the storage for virtually any configuration of storage chambers, without resorting to any manual calculations.
HydroCAD can also model almost any imaginable storage arrangement, including layered chambers of different sizes combined with auxiliary storage from adjacent pipes and catch basins, and even the above-ground areas (parking lot) that may provide overflow storage for certain events.
Modeling Terre Hill Stormwater Systems storage products
Setting up a pond to use Terre Hill storage products is a simple process: Just pick the desired model from the drop-down list, and specify the number of chambers plus their elevation. HydroCAD supports the Terre Arch 26 and Terre Arch 48, as well as the associated end-caps and manifolds.
To allow for storage in the stone backfill, first describe the shape and dimensions of the outer excavation, and set the stone voids. Then specify the chamber(s) and set them to embed within the stone. For maximum accuracy, you can also embed the associated headers and end-caps. Based on this information the composite storage is calculated automatically.
Note: The chamber wizard will automatically configure the chambers and stone bed, but the headers and end-caps must be entered separately. For details see the chamber modeling instructions.
The Terre Box can be modeled in HydroCAD as a concrete box pipe of the same size.
Modeling exfiltration and outlet control structures
To perform a complete hydrograph routing through a Terre Hill system, select the appropriate outlet controls on the "Outlets" tab. For details read about pond modeling.
Detailed product information
For detailed Terre Hill specifications and design information, please visit the Terre Hill web site.
For more information about HydroCAD
Please see the following pages for further HydroCAD information:
HydroCAD home page
Pond storage calculations
Storage chamber modeling
(includes step-by-step instructions)
Exfiltration calculations
General support page
HydroCAD features and capabilities
Free evaluation program
Pricing and ordering
Terre Arch™
and Terre Box™ are
trademarks of Terre Hill Stormwater Systems
HydroCAD® is a registered trademark of HydroCAD
Software Solutions LLC
Product illustrations © Terre Hill
Stormwater Systems