IPGC Applications, Benefits, & Comparisons

IPGC Applications

The IPGC drainage pipe is useful for multiple applications and will function efficiently as any of the drainage device(s) below.

Capturing Runoff with the IPGC

The IPGC can be installed to capture runoff from roadways, parking areas, driveways, yards, and virtually any other landscaped or natural area. The two images below indicate the most typical ways to capture runoff in sumps and on slopes. Additional images are used to demonstrate where the IPGC can be installed and provide insight into how it can be used for intercepting, capturing, and routing drainage on commercial sites and residential lots. Just use your mouse wheel to zoom in on them.

IPGC Product Benefits


  • As the length and size of the IPGC section increases, so does the open flow area on the pipe surface. Therefore, the open slit area never limits the amount of flow that can be captured. That will always depend on the actual cross sectional area of the pipe.

  • The IPGC slits will provide ample open flow area to capture runoff right at the ground surface. A standard perforated PVC pipe can only capture a fraction of the flow that the IPGC does for an equivalent pipe section. Incidentally, the perforated pipe was never designed or intended to capture surface drainage.

  • The open slits can ideally be installed just at or below the surface, depending on the anticipated amount of sediment deposition that could occur. This allows for a reduced amount of ponding to occur at the point of capture.

    A perforated pipe would peform more similarly to The IPGC if the perforations were more concentrated on the surface. The additional length of perforated pipe that would be needed, to provide the same open flow area on the surface, directly depend on the pipe diameter and the arrangement of the perforations. A fully perforated PVC pipe could also be used, but our market research shows that fully perforated PVC pipe is not readily available at most hardware stores and usually requires a custom order to get it sent or made by a manufacturer. Why go through the trouble when you can just get the IPGC?

Reduced Costs / Easier to Install

  • The IPGC will help to lower the overall installation costs by reducing the excavation quantities that are required for installing a typical drainage system.

    This is because typical drainage systems usually consist of landscape and/or grate inlets in landscaped/natural areas and storm lines that are buried at least 6-12" beneath the surface. The IPGC installation can be accomplished using a bobcat or ditch witch along with a few hand digging tools.

  • The IPGC is a great option in tight areas that could not support the use of large equipment without installing tree protection measures or possibly even having to remove trees.

  • The IPGC can serve as an effective and re-useable erosion control device could suffice in place of required controls that are not re-useable or that would require new installations for other projects. (i.e., silt fence, open diversion channels, earth sediment traps, & earth berms).

  • The IPGC can be installed to capture runoff from roadways, parking areas, driveways, yards, and virtually any other landscaped or natural area.

The IPGC Trench Drain

The IPGC drainage pipe is an effective, cost-efficient, and easy-to-install trench drain that will readily capture a substantial volume of drainage runoff right at the ground surface. The concentrated and abundant open slit area on the IPGC surface?allows for this optimization. The IPGC Trench Drain?is able to?convey the captured runoff just beneath the surface until it becomes necessary to install deeper lines. At that point, the IPGC can easily be connected to standard PVC pipe with the appropriate standard PVC fittings.

Please Note:
The IPGC Trench Drain is not and should not be confused with a typical French Drain that houses a standard perforated PVC pipe.

The following list describes several benefits of the IPGC Trench Drain not provided by the French Drain:

Other Benefits of the IPGC Trench Drain include:

The IPGC French Drain

The IPGC French drain is simply the inverted IPGC Trench Drain with the addition of a bottom gravel layer.  With the open slits facing downward, resting on top of the bottom gravel layer, the IPGC drainage pipe is able to allow substantially more stormwater into the pipe than will a standard perforated pipe. This is because of the abundant open area provided by the surface slits.  With an identical amount of contributing flow, the ponded depth above The IPGC drainage pipe will be less than that which occurs for the standard perforated pipe.  This fact can be verified with the orifice equation.

The IPGC Storm Drain

The IPGC storm drain is simply the drainage pipe itself, however, the IPGC is able to convey stormwater more effectively than a standard perforated pipe with the slits facing upward. This is because the bottom portion of the pipe remains in tact from the flowline up to the bottom of the slits.  If the IPGC is installed with the slits facing downward, as a French Drain, flow is minimally affected by small pockets between the top of the gravel layer and the inside wall of the pipe. These small pockets will hold water until final infiltration into the gravel occurs.  

The IPGC Grate Inlet & Catch Basin

The surface of the IPGC performs as a grate inlet in a sump or on-grade. The actual pipe itself will serve as a catch basin and conveyance device. When the open slits can be exposed at the surface, the open flow area is maximized.

The IPGC Interceptor &  Diversion Device

The IPGC can function as both a drainage interceptor and diversion device since it will simultaneously function as a grate inlet, catch basin, and storm drain.  Along the perimeter of a residential lot or commercial site, the IPGC can be installed to capture flows leaving or entering the property.  Once the contributing flow is captured, the IPGC can be connected to additional PVC pipe as needed in order to discharge at the desired location.

The IPGC Filtration Drain

When wrapped with filter fabric and covered with porous gravel, the IPGC is an excellent filtration drain with the following additional benefit: The additional open flow area provided by the IPGC requires a lower head (or water depth) than a standard PVC perforated pipe to convey the same flow rate. This means that the ponded depth will be lower for any given flow rate at the point of capture.

Detention Pond Outlet Drains

The IPGC is a less costly and equally effective alternative to installing typical pond outlet structures. Additionally, the required open area (for an orifice) can be provided within a tolerance area of one slit. The open width for an individual slit on all available pipe sizes is 0.25-inches. The individual open slit lengths remain constant for a given pipe size, but as the pipe size increases so will the individual open slit length.

Water Quality Pond Riser Pipes

For this application, the IPGC is merely an alternative to perforated pipe, as neither seems to have a distinct advantage or disadvantage. This is because the typical release rate from a filtration pond is small in comparison to incoming flows.

Rainwater Harvesting

The IPGC makes it relatively simple to capture surface water runoff for use in a rainwater harvesting system. The following paragraphs describe rainwater harvesting in a non-technical fashion for those interested in learning about the excellent benefits of rainwater harvesting.

Firstly, rainwater harvesting is an effective means for filtering out pollutants such as suspended particulate matter and associated constituents such as bacteria, nutrients, and metals that originate on impervious surfaces such as rooftops, asphaltic concrete, and even man-made landscaped areas.

Although most rainwater harvesting systems treat runoff that is captured from rooftops with gutters and collection pipe, it is becoming more common to capture, treat, and use runoff from impervious surface areas on a developed property. Once the runoff is captured, it is routed to a storage tank where sedimentation occurs. Storage tanks can be located above or below the ground, but this usually depends on the physical constraints and how the rainwater is to be captured and used. A pump is required for below ground storage tanks when the treated water must be lifted to an elevation where it can resume gravity flow or is dispersed. The storage tank will remain idle for a certain period of time, depending on the pump settings. Once released from the tank, the treated runoff can be used for natural infiltration, landscape irrigation, plant and lawn watering, secondary water supplies for green buildings, and reclaimed for cooling water.

The IPGC can be used for more than just capturing runoff for a rainwater harvesting sytem. It can also be used for disbursing the treated runoff in order to provide natural infiltration of an area, gravity fed irrigation, and pump-fed irrigation. The image below shows two possible rainwater harvesting systems: each has a discharge system comprised of standard and IPGC Schedule 40 PVC piping. To look at a larger image, just use your mouse wheel to zoom in on it.

Please note that these images are schematic representations and should not be used as construction details. We highly recommend that all interested parties consult with a licensed rainwater harvesting professional before installing a rainwater harvesting system at your home or business. A list of nearly 40 rainwater harvesting professionals is available from the Texas Rainwater Catchment Association Website.

The IPGC as an Erosion Control Device

When a section of IPGC is used in a sump location and is either covered with gravel or wrapped with filter fabric, very little sediment can enter the pipe. When used in this fashion, the IPGC can significantly help to minimize sediment transport in addition to removing potential pollutants from the runoff entering downstream waterways. After an unspecified period of time, especially in areas with little or no vegetation in the area contributing runoff to the sump, sediment will inevitably accumulate in the vicinity of an IPGC section. When this occurs, the displaced sediment should be removed in order to restore full functionality of the IPGC as a filtration and drainage device.

If sections of the IPGC are installed parallel to grade (or perpendicular to the direction of flow) and are placed intermittently to intercept surface water runoff, the diplacement of sediment caused by wash out can be minimized because of the flow reduction on the ground surface. If used in combination with silt fencing, the IPGC can help reduce the flow rate through the silt fence. This is desirable in situations where construction has produced an increase in runoff and therefore an increase in sediment displacement.

IPGC Comparisons

The IPGC drainage pipe will perform as a grate inlet, catch basin, and storm drain all at the same time. If the open flow area provided on a pipe surface exceeds the cross sectional area of the pipe itself, which occurs with relatively short sections of IPGC, the pipe size will dictate the amount of flow that can be conveyed. As seen in the above photo, the IPGC provides substantially more open flow area on the pipe surface than the standard perforated PVC pipe. The following text discusses several of the inadequacies associated with perforated pipe that the IPGC will effectively accomodate.

The IPGC open slits allow for an unsubmerged flow state if installed fully or partially above the ground surface at the capture point. Each IPGC open slit will perform as a one-sided weir (on-grade) or a two sided weir (in a sump) until the contributing flow is large enough to submerge the entire pipe. The point at which the IPGC open slits become submerged is dictated by several factors inlcuding the pipe size, pipe slope, and the contributing flow rate. The section length of the IPGC is another important factor as larger spans contain more open slits (or open slit area).

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