+

Q & A

Refer to the Minimum and Maximum Burial Depth per AASHTO Tech Note

Minimum cover heights are dependent on the backfill material used and the expected live loads.  For AASHTO HL-93, H-25 or HS-25 loading, pipe with diameters of 4”-48” shall have a minimum of one foot of cover, while 60” diameter pipe must have at least 18 inches of cover.  Cover heights are measured from the top of the pipe to the bottom of flexible pavement or to the top of rigid pavement.  Minimum covers assume Class III backfill material compacted to 90% standard Proctor density around the pipe and a minimum of 6-inches over the pipe crown.

For construction loading, additional backfill may be necessary.  For heavy construction loads between 30-60 tons, a minimum of 3 feet of cover shall be used.

Refer to the Minimum and Maximum Burial Depth per AASHTO Tech Note

The maximum cover is significantly influenced by the type of backfill material used and level of compaction.  Special care is necessary for deep burial depth installations.  For burial depths that exceed recommendations, contact your Prinsco Representative to review the site specific information.

HDPE is a flexible pipe that relies heavily on the strength of the embedment soil for its strength.  With the requirements for minimum cover met, HDPE pipe is rated for AASHTO H-25 loading.  Refer to the Standard Trench Installation Detail for backfill and compaction requirements.  Note that the minimum burial depth requirements for parallel pipe installations may require additional cover.  For heavier loading scenarios, contact your Prinsco Representative.

Prinsco manufactures pipe to meet the specifications of AASHTO M294 & M252 which require virgin compounds be used for the manufacturing process.  However, Prinsco has incorporated recycled resins into their manufacturing process for over 10 years and have mastered the blending process.  After years of blending technology and research, Prinsco has manufactured a product called ECOFLO® 100 that utilizes 40% recycled material and has a 100 year service life.  That kind of performance is unprecedented in a recycled product.  ECOFLO® 100 meets or exceeds the requirements of AASHTO M294 with the exception of the recycled content.

HDPE pipe meeting the requirements of AASHTO M294 or M252 is manufactured with carbon black colorant which protects the pipe from UV degradation.  Carbon black has been proven to protect pipe for years without affecting the performance.  Once the pipe is installed, the pipe is no longer exposed to UV degradation.  The exposed ends of the pipe will not be subjected to the stresses of buried pipe and are not a consideration for the effects of UV degradation.

The most common method for joining dissimilar products is to butt the ends together, wrap the connection in a non-woven geotextile wrap and pour a concrete collar around the connection.  Prinsco also offers a number of fittings and accessories including clay adapters, fabricated pipe adapters, and Marmac Couplers for joining dissimilar products.  Contact your local Prinsco representative for the best option for your application.

During pipe joint assembly, it is critical to ensure the pipe lengths are aligned both vertically and horizontally.  Improper alignment will result in difficult or improper joint assembly and may cause the pipe joint to leak.  If the misalignment is necessary for grade or curvilinear alignment, a maximum of 1 degree of misalignment is recommended.  Prinsco offers a wide array of standard and custom fittings for curved alignments.  Contact your local Prinsco Representative for more information.

Underground retention & detention systems are both designed to collect stormwater and release it at controlled rate to eliminate downstream flooding.  The main difference is between the two is the period of time the water is retained within the system.

A detention system is designed to slow and temporarily hold stormwater runoff in a contained area until it can be released at a controlled rate.  The outlet of the system is typically at the lowest point in the system, allowing the system to slowly, but completely drain.

A retention system is also designed to slow and temporarily hold stormwater runoff, however the containment pipe is perforated allowing for the water to infiltrate into the soil and recharge the groundwater table.  The outlet of the retention system is typically placed near the highest point of the system.  This allows the stormwater to flow downstream in the event of excessive or strong storms without backing up the system upstream.

Update Your Browser

You are using an outdated browser. 

For the best experience on the Prinsco website, please considering upgrading your browser.