The Stormwater Blog 

Contech Stormwater experts discussing Low Impact Development, Onsite Water Management, Rainwater Harvesting and all things Stormwater.

Entries for 'Gabe Weaver'

6 Corrugated Metal Pipe Detention Design Questions

For the majority of applications, corrugated metal pipe (CMP) is the “go to” material for subsurface infiltration. This in turn, leads to a lot of design questions. Below is a list of six questions and answers we received from a recent webinar on designing CMP detention systems.

Categories: Detention
Designing CMP Detention Systems Part Three – Design Red Flags
In our third and final part of our blog series we will look at design red flags for CMP detention systems. Red flags are design elements that are commonly or easily overlooked and may need extra attention when designing. Considering the red flags upfront will expedite the design and fabrication process, and eliminate delays, installation, and performance issues.
Designing CMP Detention Systems: Part Two – Cost Effective Design and Layout

The goal of any CMP detention system should be to maximize the vertical space available to minimize the overall footprint, to reduce material, excavation, and backfill costs. To do this we recommend using the largest diameter pipe possible.

Designing CMP Detention Systems: Part One – The Value of Going Underground
The two essential functions of a stormwater management system are to control the quality and quantity of runoff leaving a site. There are various ways to do this; a common method is with an above ground system in the form of a detention pond.
Subsurface Infiltration as a LID Stormwater Management Strategy
The only sure way to eliminate stormwater pollution is to eliminate stormwater runoff. In recognition of this fact, Green Infrastructure (GI) and Low Impact Development (LID) practices have prioritized runoff reduction as a primary regulation for stormwater management.  These practices have proliferated throughout the United States.


Is Corrugated Metal Pipe Suitable for Subsurface Infiltration?
Some engineers are hesitant to use CMP (corrugated metal pipe) for stormwater applications because they have read or heard about CMP being used in culverts that have corroded. This shouldn’t be the case. Many decades ago, galvanized pipe was the coating of choice for culverts; that now has been replaced with Aluminized Type 2 (ALT2). 
Stormwater Infiltration Explained

Stormwater infiltration is defined as the process by which water enters the soil and recharges streams, lakes, rivers, and underground aquifers. Stormwater infiltration is a fundamental component of the water cycle and is quickly becoming the centerpiece of stormwater management strategies across the United States. Stormwater infiltration is an effective means of managing runoff because it allows practitioners to address both water quality and water quantity concerns.

Thinking Outside The Box: Infiltration System Layouts
Historically, underground infiltration beds have been laid out in either square or rectangular shapes, sometimes far away from where the actual rain drops fall. These large systems are typically fed by a series of upstream catch basins and conveyance pipes. Several factors contribute to site layout, but mostly it simplifies the hydrologic and hydraulic modeling process, and keeps infiltration beds away from more sensitive underground infrastructure.
Three Components of Infiltration System Design
Common infiltration practices include drywells, bioretention, permeable pavement, infiltration trenches, infiltration basins, and subsurface infiltration galleries. Regardless of their form, all infiltration systems have three primary components: storage, treatment, and infiltration.
Categories: Infiltration

Stormwater Blog Update Hubspot subscription form

We respect your privacy,
your email will only be used to send
Stormwater blog updates.