Flow Isolation

 

EST performs flow Isolation in sewer lines where groundwater has been determined to enter the sanitary sewer in significant quantities. Isolation of groundwater is performed during the early morning hours (Midnight to 6:00 a.m.), when residential usage is at a minimum. Portable pipe weirs are placed in the targeted sewer lines to measure the flow in segments of approximately 300 linear feet. The flow volume is calculated in order to isolate the areas contributing significant infiltration.

Contact us today to request a quotation or learn more about EST’s flow isolation capabilities.

Flow Isolation FAQs

Why is flow isolation only completed at night?

Flow Isolation is typically performed during early morning hours (midnight to 6am) when residential usage is at a minimum.  During this time, it is not uncommon for EST field crews to observe significant volumes of clear water flowing thorough the sewer lines, a strong indication that large amounts of groundwater are entering the sewer system.  By isolating line segments and measuring these flows, it is possible to quantify infiltration into the sewer system.

How will the flow be measured?

Portable volumetric weirs will be placed in targeted sewer lines to measure the flow. The flow volume will be calculated in order to isolate the areas contributing significant infiltration. 

How are measurements taken in large diameter pipes?

Insert weirs can be used to accurately measure wastewater flows in pipes up to 18″ in diameter.  Depth and velocity measurements are typically collected in larger pipes in order to calculate flow rates.

New England Office

124 Crescent Road, Needham, MA 02494

Mid-Atlantic Office

127-G Gaither Drive, Mount Laurel, NJ 08054