Dewatering Bags to Pump Manholes

Dewatering Sediment Filter Bags

dewatering bagQuestion: regarding dewatering bags to pump manholes. The company I work for has to pump out manholes which just can't be dumped into the storm sewer. One of the cities recommended dewatering bags.

I found your site through Google. What is the dewatering bag size you would recommend? What is the pump flow rate I have to use for the required bags?

Answer: Thank you for contacting us! Dewatering bags are offered in a couple of different sizes, typically dewatering bags to pump manholes can be chosen based on either the flow of water being pumped into the bag or the amount of sediment that you will need to contain. Standard sizes for these bags are as follows:

  • 6 feet by 6 feet:
    • Capacity of 1.44 cubic yards

  • 15 feet by 10 feet:
    • Capacity of 6 cubic yards

  • 15 feet by 15 feet:dewating bag
    • Capacity of 9.6 cubic yards

  • 15 feet by 20 feet:
    • Capacity of 12 cubic yards

  • 15 feet by 25 feet:
    • Capacity of 15 cubic yards

  • Custom sizes available on request

Questions? We can help! Call our team at 1-772-646-0597 or submit a form.

These dewatering bags to pump manholes come with two different fabrics: 8 ounce and 10 ounce. The 8 ounce fabric allows for flows up to 80 gpm while the 10 ounce fabric allows for flows up 60 gpm.

Other Dewatering Bag Considerations

Other considerations you will want to take into account when choosing a dewatering method can be seen in the list below. Taking all these options into consideration can help us determine the size bag you will require for dewatering of your site. A full questionnaire can be mailed to you upon request for a more detailed account.


  • Percent of Solids in Situ
  • Goal Percent Solids
  • Will Polymers be used?
  • How much Space is Available
  • Pumping Rate
  • Duration of the Project

Read about other customers asking about using Dewatering Bags to Handle Septage

Comments Regarding The Project Dewatering Bags To Pump Manholes:
GEI Works Team, March 25, 2012
Reference: Dewatering Bag Sizes Are Dependent On The Pump Flow Rate

Thank you for asking. Normally folks use the smaller fifteen feet x fifteen feet size dewatering bags for that but it is dependent on the pump flow rate.
A two inch trash pump (fifty millimeter) for example will run 100 - 200 gpm so the fifteen feet x fifteen feet or the ten feet x fifteen feet will work well.

We have those silt bag sizes in stock.
Happy to help.

David, Aug 16, 2011
Reference: Dewatering Bags

In reference to dewatering bags used for sanitary sewer operations- most all dewatering bags are constructed with fine mesh and will allow sewage and other liquids to escape the bag upon use. What manufacturers need to make is a dewatering bladder, where liquid will not escape, [as similar with liquid storage bladders] but they need to be designed so that, a pump hose can be connected, the sewage liquid flows into at x elevation, the sewage sediment large particals and possible soils suspended, flows through mesh baffle then an exit hose can be attached at higher allow out going flows to a sewer manhole. This way, if you are pumping mixed sewage/ground water, to a manhole, you can filter out some of the sand, dirt and other things which clog a sewer or storm drain and meet the federal and or state regulations and not affect storm inlets or create sewage runoff reportable quantities.

Give us a call at 1-772-646-0597 or fill out our quote request form to discuss your requirements.