Hire the best Roofing Expert

100 year rain event

Results 1 to 13 of 13
  1. #1
    4K Club Member
    Join Date
    Nov 2009
    Location
    Geelong
    Posts
    6,207

    Default 100 year rain event

    Just now.
    We seem to have had a supercell centered over our house for at least half an hour and the gutters and downpipes could not cope.
    Am I right in thinking that once the 100mm main pipe to the street is full that there isn't much more that could be done?
    Our back yard is awash from fence to fence and I am dreading the clean up in the morning.
    Yet a few hundred metres away there was only a light sprinkling.
    Shade sails are sagging with the weight of hail trapped in them.
    Is it really possible to design for storm cells such as the one that just passed over us?
    Cecile has a video of one downpipe overflowing where we are still waiting for the plumber to come back and finish the job he postponed until we finished the cladding.
    "A big boy did it and ran away"

    Legal disclaimer denying responsibility to be inserted here.

  2. #2
    1K Club Member
    Join Date
    Mar 2010
    Location
    Geelong
    Age
    66
    Posts
    1,765

    Default

    Not sure if this link will work but this is about ten minutes in. The D/P isn't glued at the bottom and it simply geysered out. Surprisingly though, the short wall we put up to protect the outdoor laundry actually works, and the washing machine is completely dry on top.

    https://www.facebook.com/676348133/v...7188294578862/
    I am not responsible for anything that Moondog says!

  3. #3
    7K Club Member
    Join Date
    Jun 2010
    Location
    Geelong
    Posts
    7,785

    Default

    Link didn't work for me, Cecile. May need to be set to Public in FB

    Looking at BOM radar, looks like the cell is about to slide by my place by about 500m

    Stay safe!

  4. #4
    1K Club Member
    Join Date
    Mar 2010
    Location
    Geelong
    Age
    66
    Posts
    1,765

    Default

    OK I changed the audience so it may or may not work. Was chaos out there for about 45 minutes. Lots of water lying around on the driveway but presumably no damage. Ted hasn't checked the garage yet to see if it stayed dry.
    I am not responsible for anything that Moondog says!

  5. #5
    7K Club Member
    Join Date
    Jun 2010
    Location
    Geelong
    Posts
    7,785

    Default

    Yep, link worked this time. That's quite the gusher

  6. #6
    3K Club Member
    Join Date
    Jun 2012
    Location
    Sunshine Coast
    Posts
    3,647

    Default

    1 Downpipe drops/pops are not good at getting rid of water in a hurry.
    2 Hail being ice blocks the drops/pops and fills the gutter so the water has nowhere to go but over the side.
    3 Looks like the drains are not capable of taking the flow you got, that is if the drain in the video actually goes anywhere,but I have seen 450 mm dia drains back up in downpours.
    Friends further up the coast have downpipes which go into the sand and gush out every time it rains.
    Does not say much for building certifyers.

  7. #7
    4K Club Member
    Join Date
    Nov 2009
    Location
    Geelong
    Posts
    6,207

    Default

    That's 100mm SWV and leads to the legal point of discharge at the curb, the downpipes are 80mm and all the pops have brushes fitted but we still had some piles of hail around the area at 10AM. Cecile had the gutters cleaned just on a month ago too.
    "A big boy did it and ran away"

    Legal disclaimer denying responsibility to be inserted here.

  8. #8
    3K Club Member
    Join Date
    Jun 2012
    Location
    Sunshine Coast
    Posts
    3,647

    Default

    Quote Originally Posted by Moondog55 View Post
    That's 100mm SWV and leads to the legal point of discharge at the curb, the downpipes are 80mm and all the pops have brushes fitted but we still had some piles of hail around the area at 10AM. Cecile had the gutters cleaned just on a month ago too.
    If the water in the kerb is up to or above the top of kerb, that will cause a considerable slow down in flow of the drain.
    Also if the drains were laid then run over by machines/cars/trucks etc ditto above.
    Brushes ??? will also cause a slow down in flow.
    As for gutter cleaning I have seen 4 pine needles block a drop/pop to the extent the gutter overflows.

  9. #9
    4K Club Member
    Join Date
    Nov 2009
    Location
    Geelong
    Posts
    6,207

    Default

    When I drove down the street the morning after there were piles of hailstones by the side of the road at 10:00AM, and we still had hailstones piled in the middle of one shade sail; I'm beginning to think that this might have been locally a one in a thousand year event. Certainly all the gutters and roads were overflowing.
    "A big boy did it and ran away"

    Legal disclaimer denying responsibility to be inserted here.

  10. #10
    Community Moderator phild01's Avatar
    Join Date
    Aug 2009
    Location
    Sydney, north
    Posts
    15,969

    Default

    Quote Originally Posted by Moondog55 View Post
    I'm beginning to think that this might have been locally a one in a thousand year event.
    You might find they are becoming far more regular than that. Sydney seems to be getting much more of this then ever before. Think about all that air rushing around the planet now with temperature extremes.

    https://www.abc.net.au/news/2021-10-...arns/100540012

  11. #11
    3K Club Member
    Join Date
    Jun 2012
    Location
    Sunshine Coast
    Posts
    3,647

    Default

    Quote Originally Posted by phild01 View Post
    You might find they are becoming far more regular than that. Sydney seems to be getting much more of this then ever before. Think about all that air rushing around the planet now with temperature extremes.

    https://www.abc.net.au/news/2021-10-...arns/100540012
    Do you think it is hot air from all the forums ??

  12. #12
    Slow but rough Uncle Bob's Avatar
    Join Date
    Nov 2007
    Location
    North Cooma, Canberra
    Posts
    5,108

    Default

    Quote Originally Posted by phild01 View Post
    You might find they are becoming far more regular than that.
    I totally agree, in Canberra, it's more a 100 day event now. We're been getting more and more rain/hail storms like you'd expect in the topics.

  13. #13
    4K Club Member Marc's Avatar
    Join Date
    Jul 2003
    Location
    Sydney
    Posts
    13,750

    Default

    I find the expectation of weather to be immutable rather amusing.
    Weather events have been changing in intensity and frequency forever, and will continue to do so.

    Hailstorms are the most localised weather events. You can have catastrophic hail in one narrow corridor of 100 meters, that is what makes hail insurable.
    The weather has been changing from year to year for milenia. The modern day concept that we can blame someone for this is equally amusing.
    Science is never settled,
    it advances one funeral at the time.
    Max Planck

Similar Threads

  1. Happy New Year!!
    By Uncle Bob in forum Announcements
    Replies: 8
    Last Post: 3rd Jan 2019, 02:24 PM
  2. Five year wait!
    By Melburn in forum Owner Builder’s Forum
    Replies: 17
    Last Post: 26th Jun 2018, 12:12 PM
  3. Happy New Year
    By Uncle Bob in forum Announcements
    Replies: 9
    Last Post: 4th Jan 2015, 03:43 PM
  4. Happy New Year
    By friedrice in forum Introduce Yourself
    Replies: 0
    Last Post: 31st Dec 2010, 06:04 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •