We were called out by Parkhaven Trust to
one of there sites to attend to a blocked
drain backing up the drainage system and
flooding the site. Soon after arrival we
realised this was no ordinary blockage.

We began by high pressure water jetting a
blocked manhole to the rear of the site,
heading out towards some trees and
vegetation. After extensive jetting the drain
refused to clear even after jetting the drain for 50mtrs. It became apparent the
drain was blocked further downstream so we needed a change of plan.



After failing to restore flow with our
conventional jetting unit and considering the
distance of the drainage run, we decided this
may be a job for our high pressure tanker jet
unit which would provide more power to
clear the blockage.
Soon after jetting we were hit a solid
obstruction approximately 100mtrs
downstream, but still the blockage refused
to budge.

Our sonar location device was sent down the
manhole to determine the point of
obstruction for further investigations. The
position of the obstruction was traced to
the trees at the back perimeter of the
site. After shuffling in some undergrowth
a hidden manhole was discovered.








We then continued tanker jetting from the
hidden manhole where the drain changed
directing out towards adjacent fields. Finally
after further jetting we were able to restore
flow to the drainage system, emptying all
manholes around site.








After clearing, we were concerned
there may still be a problem with the
drain that would cause blockages to
return, so we advised the
client that a CCTV inspection would be
sensible to assure there was no
underlying problem.
CCTV surveillance identified a large piece of wood
lodged in the drain downstream from the hidden
manhole. We believe this was the direct cause of the
blockage so further action was unavoidable.





Rather than implementing an
excavation to physically remove the
piece of wood, we decided to try and
retrieve the wood using the tanker jet
unit saving costs and further disruption.
Luckily due to the high power of our
tanker unit we were able to dislodge
the piece of wood and wash it back to the manhole for
removal, in turn providing the drain with a clean bill of
health.











John McGee Estate Manager had this to say...

"I have used the services of A1 all clear over the past eight years, they have
always responded to our calls for assistance without delay. I have needed
there assistance with some particularly unusual problems, drain diversions and
serious blockages, which had they not been resolved quickly could have had a
serious detrimental effect on our business, but for the determination and
professionalism of their engineers, who have always stuck with the job until it
has been resolved."

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