Soak holes – The worker bees of a stormwater management plan

Posted by Dutton Stormwater on

The Auckland Region has large pockets of free-draining volcanic and basalt rock under the ground called puros. Stormwater Management Plans often take this into account, and specify a soak hole as the final point of drainage for a site.

Soak holes are usually a standard manhole with deep bores (minimum 1m) which vary in diameter. These bores are drilled into the earth and are encased with a PVC pipe. There is a siphon sitting on the PVC Pipe which is below the invert of the inlet pipe.

Drawings are taken from Auckland Council Website. 

How does a Soak Hole work to control runoff?

Stormwater enters the soak hole and water is siphoned down the bore with any solids being caught on the grill of the siphon.

What could cause a soak hole to block up?

Plastic bags and litter can get stuck over the grill of the siphon.

The siphon can get knocked off and a bottle or other solid item get stuck down the bore not allowing water to drain away.

Silt can build up on the bottom of the sump and eventually fill up the bore which not allowing any drainage.

To avoid blockages and hence flooding, it is imperative soak holes are maintained.

What does Dutton Stormawater’s Soak Hole maintenance involve?

  • Prior to the service we contact you to schedule a specific date for the service to take place.
  • During the service we:
    • vacuum the silt off the floor of the soak hole
    • remove any litter and debris
    • waterblast and flush the bores
    • clean and replace any siphons that have fallen off the bores.
  • After the service you will be sent a report for your records.

Soak Hole Maintenance is recommended annually.

Call us for a free, no-obligation quote.

From the Director’s desk – June 2020

Posted by Dutton Stormwater on

I often use metaphors to explain how I see a situation. I mentioned to the team on 24 March that I felt we were like an army platoon enclosed by a great wall, walking in darkness toward a tiny distant light. I knew our platoon would emerge from this crisis shining and strong – and we have. We have broken through the wall with our heads held high, not consumed by what other companies are doing, rather focused on our own game.

As we emerge from Lockdown, I applaud our country and government for helping us, and am proud to say:

  1. From 1 July 2020 we are the official contractor to Auckland Council Healthy Waters for Treatment Devices, Auckland-wide.
  2. We have promoted two innovative and talented individuals: Claire Story to Office Manager and Sonny Chan to Quality, Environmental, Health & Safety Manager.
  3. An A3 7000l vacuum truck is on order, to be delivered in October.
  4. Despite the knocks and challenges of Covid19, all Dutton Stormwater staff have retained their positions.

I feel proud of how Dutton Stormwater has operated throughout this crisis and am proud of each of you for being brave and kind.