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  1. BernieH

    Xing under AC Main

    Anyone know the feasibility of crossing under a 1970's 8" AC Water main at right angles to install a sewer - without causing the AC main to leak in the process? Thanks
  2. BernieH

    Reservoir Sizing for Fire flows

    (1) There have been situations where multiple fires were burning simultaneously in a particular pressure zone. So why is there apparently (in my research) never a requirement to increase reservoir fireflow storage based on the area or population served? (2) have municipalities found their...
  3. BernieH

    Required thrust lengths overlapping

    I'm looking at the situation described in the attached, where valve A and valve B are both closed. Pressure beyond each valve is zero. Treating each end of the pipe as a dead-end, the required thrust restraint lengths overlap. However, all forces oppose each other. So if I restrain the...
  4. BernieH

    Restraint at Tee, Branch valve closed

    I'm considering the case of thrust restraint near a tee, where the branch valve is closed, the branch is pressurized and the run is not (see attachment). DIPRA covers this situation in their FAQ's at http://www.dipra.org/faq/thrust.cfm They say that the pipline on the unpressurized side of the...
  5. BernieH

    Thrust block curing time

    AWWA stipulates that thrust blocks must cure for 5 days before a water main is pressure tested (unless high-early is used). However, I understand that some contractors are routinely pressure testing immediately, without waiting for curing to occur. What is your experience with what is actually...
  6. BernieH

    Why both restraints and thrust blocks?

    Why is it that some municipalities demand both joint restraint and thrust blocking? I guess thrust blocks can be altered or removed during subsequent work on other utilities. So backing up thrust blocks with restraints could make sense. But why should restrained joints be backed up by thrust...
  7. BernieH

    Inter-zone Bleed for Water Quality

    Thanks for the responses, they were helpful
  8. BernieH

    Inter-zone Bleed for Water Quality

    In order to avoid creating a dead end at a pressure zone boundary, I would like to install a connection between the higher zone and the lower zone. Rather than using a PRV that would close during times of low flow, I think people sometimes use a very small connection between the two zones...
  9. BernieH

    Flexibility Concerns when Connecting Watermains to Appurtenances

    Could someone also advise me on joint flexibility? I understand a mechanical joint has some flexibility to it. So connecting an appurtenance such as a gate valve to a watermain using a mechanical joints is probably straightforward. But a flanged joint is rigid, so if a gate valve is connected...
  10. BernieH

    Reading Watermain Designs

    Thanks for your thoughts on these abbreviations. I've got another question about joint flexibility, but I'll put it in a new thread.
  11. BernieH

    Reading Watermain Designs

    Could someone please tell me what H and F stand for in these watermain design specifications? Gate Valve 300FxH 22.5 Bend 300dia. HxH End Cap 150H Also, what does "Mech CPLG 150" stand for? Thanks
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