link to page 2 link to page 14 link to page 39 link to page 41 link to page 42
Table of Contents
1.
1. Paremata Wastewater Update Email
1
2.
2. Paremata Wastewater Rising Main
13
3.
3. Copy of Aotea pipe breakParamata overflow Enteroccoci monitoring (cfu100mL)
38
4.
4. Email correspondence between WWL and PCC
40
5.
5. Email correspondence between PCC and WWL
41
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UPDATE 19 20:30 25 July 2021
Good Evening
The team were successful in completing the repair this evening and the rising main is now
operational. Our team will be monitoring the repair overnight. Note that we will still have some
carparks coned off in the turning circle of the carpark due to machinery being onsite for monitoring
purposes. Please see the picture below for approximate location of pumps (in blue) and carparks in
red.
The principal of Paremata School has been advised that we will have Station Road open with traffic
management operators on site to assist parents at pick-up and drop-off time.
Below is a media statement which is being released at approximately 21:00.
Attribute to Steve Hutchison Chief Advisor Wastewater, Wellington
Water
Our crews have completed the repair to the burst wastewater main between the
Aotea turnoff and Paremata.
While the repair has been successful and has enabled us to begin reusing the
main, our investigations have shown that it remains in a very poor condition. We
are continuing to investigate the extent of this while exploring options for a
permanent replacement or repair.
As the bursts caused wastewater to overflow, on Saturday 24 July, a rāhui (ritual
prohibition) was put in place by Ngāti Toa, banning the taking of shellfish or fish
in and around Porirua harbour. It will be in place for two weeks.
State Highway One, northbound, will remain reduced to one lane while work to
clear the site continues. Traffic management will be in place, off peak, while we
do this. Some car parks at the end of Station Road, by the service station, will
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also be coned off while pumps remain on site, as a contingency. Please avoid the
area if possible.
Further information on recreational water quality is available at lawa.org.nz.
We’d like to thank the public for their continued patience while we work to fix
this issue.
Media conta
ct: [email address] or 021 302 259
Kind regards
Glenis
UPDATE 18 12:30 25 July 2021
Good afternoon
The team are working hard on the repair today and works are progressing well. Because of the
complex nature of the repair it is anticipated we will be working into the evening.
Overnight there was no discharge into the harbour. The rising main was kept in operation and
excess flow was well controlled by the use of sucker trucks. The rising main has had to be taken
offline to make the repair today and we are using sucker trucks to minimise overflow although there
has been some discharge to the harbour.
Traffic Management remains in place and we are liaising with Capital Journeys. Currently the
carpark at the railway station is closed and we will advise when this is open for use again.
A further update will be provided in the early evening.
Thank you for your patience and we apologise for the inconvenience.
Kind regards
Glenis
UPDATE 17 11:25
Good morning
Unfortunately there has been a delay in the arrival of the specialised fittings from Auckland, which
will now arrive after 21:00 (9pm) tonight. Consequently we are putting today’s work on
hold. Sucker trucks have been mobilised to assist with minimising overflows at peak times and work
will resume tomorrow morning.
Thank you for your patience and we apologise for the inconvenience.
Kind regards
Glenis
UPDATE 16 11:10 24 July 2021
Good Morning
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Works are continuing today at the Rising Main repair on SH1 Paremata. Repairs today consist of
replacing a longer (12 meter) section of pipe in the area with specialist internal reinforcement joints
which have been sourced and flown in from Auckland to enable connection to the fragile pipe. This
work is expected to continue into the evening.
Flows were contained overnight with no overflows to the harbour. Leakage from the repair site was
contained by the use of sucker trucks. We anticipate there may be some overflows today while the
repair work is underway. Sucker trucks have been mobilised to reduce the overflow, however there
are likely to be some overflows during peak times today.
Ngati Toa are planning to place a Rahui on the harbour area which will be conducted at the Titahi
Bay Boating Club at 1pm today.
Sampling is continuing and we are liaising with GWRC to keep recreational water advice updated on
lawa.org.nz.
A media release will be going out at 11:30 (see below).
Attribute to Steve Hutchison Chief Advisor Wastewater, Wellington
Water
Our crews are continuing to work on a repair to the burst wastewater main
between the Aotea turnoff and Paremata.
State Highway One, northbound, will be reduced to one lane over the weekend
while work continues.
Traffic management is in place and we encourage the public to avoid the area if
possible.
Our investigations have shown the pipe, which has failed twice this week, is in a
very poor condition. Staff and machinery were on site overnight to monitor the
situation.
We are continuing to investigate the cause and extent of the degradation while
exploring options for a permanent replacement or repair.
Due to the complexity of the repair, and fragile nature of the pipeline, we expect
there to be some additional overflow today. We are working to minimise this as
much as possible.
To reduce potential wastewater overflow, we ask residents in Whitby, Paremata,
Plimmerton, Pukerua Bay, and in the northern parts of Papakowhai to minimise
water use as much as possible.
We ask members of the public to avoid contact with water in the area and to not
gather shellfish in the area. Health warning signs are in place.
Further information on recreational water quality is available at lawa.org.nz.
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We’d like to thank the public for their continued patience while we work to fix
this issue.
Media conta
ct: [email address] or 021 302 259
Kind regards
Glenis
UPDATE 14 – 20:15 – 23 July 2021
Good Evening
Due to the complexity of the job, fragility of the pipe and the fact that several different options have
considered and tried today, our team have made a temporary repair to hold the pipe overnight
whilst they arrange for resources to enable a more robust repair to be undertaken tomorrow.
The majority of the teams have been stood down for the night but we have people on site to
monitor the situation throughout the night. Some leakage is expected from the temporary repair
and we will endeavour to contain that using sucker trucks.
One lane of the State Highway northbound will remain closed.
We will provide a further update tomorrow morning.
Thank you for your patience and we apologise for the inconvenience.
Kind regards
Glenis
UPDATE 13 - 17:45 – 23 July 2021
Good Evening
Work to repair the wastewater main between the Aotea turnoff and Paremata is continuing.
Traffic management has remained in place through rush hour and the disruption has been
manageable.
Due to the condition of the pipe and the complex repair it’s taking longer than anticipated to
complete. We do not expect to be able to complete a permanent repair this evening and will
evaluate whether work will continue tomorrow depending on the effectiveness of the repair tonight.
Close attention is being paid to fatigue of our staff and contractors.
We will update you further later this evening.
Kind regards
Glenis
UPDATE 12 – 14:00 23 July 2021
Good afternoon
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Repair work on the rising main is progressing but has not yet completed. We are liaising with Waka
Kotahi to get the site clear as soon as possible for the afternoon peak traffic flows.
Please note that the repair work is complicated and we may have to continue work tomorrow
depending how the repair holds.
We will provide a further update following the next status meeting later this afternoon.
Kind regards
Glenis
UPDATE 11 – 09:30 23 July 2021
Good Morning
Work continued overnight in preparation for repair of the Paremata rising main and enabled us to be
track for repair today. Crews are now established on site to commence excavation and sucker trucks
deployed at key sites to minimise discharge during the course of repairs. Due to the fragile nature of
this pipe the repair is complicated and further failures are possible. We will make all efforts to
contain wastewater however expect some overflow is likely to occur.
The leaking rising main was kept in limited operation overnight and with the assistance of sucker
trucks working through the night contained further wastewater discharge from the stormwater
network overflow point beneath the Paremata railway bridge crossing.
The cross harbour pipeline was put into emergency operation for a short period overnight which
identified a leak further south towards Onepoto which required recommissioning to be abandoned.
An overflow into the adjacent stormwater sump did occur for a short period, pumping was ceased
which stopped the overflow and the site cleaned up and signage placed. This fault is being
investigated today and repair work will be undertaken when possible.
North bound traffic is currently reduced to one lane on SH 1 while repairs are
being undertaken. We are asking residents in the area to minimise water use to assist with our
efforts to minimise overflows.
We are sending the below update at 9.45am to media and uploading to our website and social
media platforms.
Attribute to Steve Hutchison Chief Advisor Wastewater, Wellington
Water
Our crews are making further repairs this morning to the burst wastewater main
on State Highway One, northbound, between the Aotea turnoff and Paremata.
To reduce potential wastewater overflow, we ask residents in Whitby, Paremata,
Plimmerton, Pukerua Bay, and in the northern parts of Papakowhai to minimise
water use as much as possible.
We are making all efforts to contain wastewater, but due last night’s heavy rain
fall there was some overflow into the harbour.
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Due the complexity of the repair, and fragile nature of the pipeline, we expect
there to be some additional overflow today. We are working to minimise this as
much as possible.
Traffic management is in place and we encourage members of the public to
avoid the area.
We also advise members of the public to avoid contact with coastal water in the
area.
The latest advice on recreational water quality can be found at lawa.org.nz
Thank you for your patience and we apologise for the inconvenience.
Kind regards
Glenis
UPDATE 10 - 19:05 22 July 2021
Good evening
Below is a media release regarding a further burst on the 525mm main.
Attribute to Steve Hutchison Chief Advisor Wastewater, Wellington Water
We are currently responding to a burst wastewater main on State Highway One,
northbound, between the Aotea turnoff and Paremata.
Traffic management is in place and we encourage members of the public to
avoid the area if possible.
This pipeline previously burst last Saturday and a repair was carried out on
Sunday evening.
Despite the repair, our investigations showed the pipeline was in a fragile
condition, and this evening’s heavy rainfall has caused a further failure.
Some wastewater is overflowing into the harbour and work is underway to
minimise this overflow.
Our crews will be preparing throughout the night to undertake a further repair in
the morning.
We advise members of the public to avoid contact with coastal water in the area.
The Incident Response team will be meeting later this evening and further updates will be provided.
Kind regards
Glenis
UPDATE 9 17:45 21 July 2021
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Good Evening
The clean-up of the walking track has been completed today. Contractors will continue working on
the walking track and Station Road tomorrow to enable us to conduct a CCTV investigation of the
Cross-Harbour Pipeline. The walking track will be reopened to the public once contractors have
finished their machine works.
Arrangements have been made to transition the current portable pump set up at Station Road to
align with the Cross-Harbour Pipeline being offline and its effect on the existing pump stations. This
will be done before the school holidays end this weekend to minimise impact on the Paremata
School. The school has a side entrance off Station Road.
The next update will be provided once pressurised testing has been completed.
Kind regards
Glenis
UPDATE 8 – 15:48 Tuesday 20th July
Good afternoon
In taking pressure off the Paremata rising main, we recommissioned the cross-harbour pipeline
from Station Road to Onepoto. In doing this, a blockage occurred on the walking track (Onepoto
side), resulting in overflow into the Harbour for under two hours. In response, the pumps were
turned off and the flow diverted back to the rising main.
This means that the rising main continues to operate under stress and we are monitoring the
situation. We have ordered additional fittings to enable further repairs.
We will also work towards making the cross-harbour pipeline serviceable by pressure testing with
potable water, as a viable alternative to the Paremata rising main should it be needed.
The walking track has been temporarily closed.
Kind regards
Glenis
UPDATE 7 – 15:05
Good afternoon,
We have now completed the repair and backfilled the excavation, which has contained the discharge
of wastewater.
It has been identified that the condition of the AC main is in very poor condition and likely to fail at
some stage in the near future.
To manage this risk, we are arranging for specialised repair fittings and pipe to be available on site.
Temporary mobile pumps have been established in Station Road to manage any high wet weather
overflows that may occur.
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The two north bound lanes on State Highway 1 will be open this afternoon by 3:30pm.
Thank you for your patience and we apologise for the inconvenience.
Kind regards
Josh
UPDATE 6 – 15:45
Good Afternoon
We’ve made good progress on the repair to the wastewater pipe in Paremata with the pipe
excavated and the new pipe being installed now.
The work involves digging a trench in the SH1 median strip, removing the damaged section, and
replacing it with a new pipe, then infilling and cleaning up the area ready for north lane of SH1 to be
reopened.
While we’re expecting to be able to complete the repair today, we’re going to need to revisit the site
to complete some tidy up work. This will be carried out in the next week and during off peak traffic.
A further update will be provided approximately 18:30 this evening.
Thank you for your patience and we apologise for the inconvenience.
Kind regards
Glenis
UPDATE 5 – 13:15
Good Afternoon
We currently have 4 pumps on site at Station Road pumping to the stormwater over flow point,
Station village pump station pumping through the Cross Harbour Pipeline as well as 12 Wastewater
tanker trucks carting from upstream to Porirua City Centre pump stations. This has enabled us to
control the flow of wastewater at the burst site sufficiently to commence repairs.
We are now starting on the excavation work in preparation for the repair of the pipe.
Further updates will be provided as the work progresses during the afternoon and early evening.
Kind regards
Glenis
UPDATE 4 – 11:10
Good Morning
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We’ve had sucker trucks on site helping to reduce the overflow to Porirua Harbour and keep
contaminated water away from Paremata school. Overnight they have managed to keep up with the
flow with less rain and stormwater infiltration into the network.
Work continued overnight on diverting the wastewater flow through an emergency line underneath
the harbour. This line was successfully opened, and some wastewater diverted through it to relieve
the pressure on the broken main. As the main could not be fully isolated repair work was unable to
be completed. Additional pumps are being installed to assist with the diversion of the flow.
This work has been challenging due to heavy rainfall and high levels of stormwater infiltration into
the wastewater network.
Today:
Contractors are on site again today working towards an urgent repair on the Rising Main.
This involves digging a trench in the SH1 median strip, removing the damaged section and replacing
it with a new pipe.
As we need the pipe to be drained when we do this, the timeframe is dependent on the weather and
the amount of infiltration we experience due to rainfall.
We hope to complete the permanent repair completed today before the rain starts again later
tonight.
Works are expected to go into late evening tonight. A no swimming notice has been put up onsite
near the harbour entrance which will remain in place for 48 hours after the overflow stops.
We’re also asking residents in Whitby, Paremata, Plimmerton, Pukerua Bay, and in the northern
parts of Papakowhai to minimise water use as much as possible.
To work on the repair, State Highway 1 has been reduced to one lane north bound (between the
Aotea turnoff and Plimmerton, 200 meters north of Aotea intersection).
We’re asking people to find alternative routes or delay travelling if possible.
The Incident Response Team is meeting regularly and I will be sending out updates as the work
progresses today.
Thank you for your patience and we apologise for the inconvenience.
Kind regards
Glenis
UPDATE 3 – 17:30
Good Evening
Our crews have been onsite all day working to fix the burst rising main on SH1. This work has been
challenging due to the continued heavy rainfall. We are currently undertaking temporary works to
direct the wastewater flow from the main through the Cross Harbour Pipeline as an alternative path
to the treatment plant outfall.
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Our teams will be working through the night to carry out a temporary repair of the rising main with
the aim to implement the permanent repair tomorrow once the rain has eased.
Traffic is very congested currently in the affected area of SH1 (between the Aotea turnoff and
Plimmerton, 200 meters north of Aotea lagoon).
We’re asking people to find alternative routes or delay travelling if possible.
Signs have been placed to warn people to avoid swimming in the Porirua Harbour and Social Media
has warnings for pedestrians to avoid any local areas with surface flooding as this could contain
some wastewater overflow.
We’d like to thank the public for their continued patience while we work to fix this issue.
Kind regards
Glenis
UPDATE 2 – 15:30
Hi All
Work continues on the burst wastewater rising main. Contractors are on site and sucker trucks are
operating to assist in reducing the overflow. Below is the media release sent out at 15:30 this
afternoon.
Update – 3.30pm
Further investigation by Wellington Water around the burst wastewater main on SH1 in Paremata
has found that the incident has also caused a wastewater man hole to overflow wastewater on to
Station Road, Paremata Crescent and on some areas near the entrance of the Paremata Primary
School grounds.
We are asking pedestrians to take extra care and avoid these areas.
We have a team on the ground who have cordoned off these areas with cones and people on site
with signage. We also have suction trucks working in this area to control flows.
ENDS
The Incident team will be meeting again approximately 16:30 and we will provide a full update
following that meeting.
Kind regards
Glenis
UPDATE 1 – 11:30
The Incident Response Team has met and work is underway to excavate and repair the broken
pipe. A media release is going out now and is shown in it’s entirety below:
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Media Release
Wastewater main burst on State Highway 1 in Paremata
Public are being asked to expect delays on State Highway 1 (SH1) in Paremata and avoid swimming
in the Paremata harbour due to a burst wastewater main between the Aotea turnoff and
Plimmerton, 200 meters north of Aotea lagoon.
Wellington Water was called out to a burst wastewater main on SH1 around 8am today.
“This has caused wastewater to overflow across SH1 and into the Paremata harbour. State Highway
1 is currently down to one lane north bound and people should expect delays,” says Sam Lister,
Wellington Water’s Manager Customer Planning.
“There are nine wastewater tanker trucks on site which is helping to reduce the overflow on SH1 and
crews are planning to do an urgent repair.”
Works are expected to go into late evening tonight. A no swimming notice will be put up onsite near
the harbour entrance which will remain in place for 48 hours after the overflow stops.
“With the heavy rainfall likely to cause more overflows, we’re also asking residents to conserve
water as much as possible.
“We’d like to thank the public for their patience as we work to repair the burst.”
ENDS
Further updates will be provided as work progresses on the repair.
Kind regards
Glenis
BURST WASTEWATER RISING MAIN
Response: Level 4
Response Lead: Sam Lister
Supported by: Service Delivery Team
Kia Ora Koutou
The 525mm diameter Wastewater Rising Main on SH 1 has ruptured. At this stage we are planning
to do an urgent repair. There is currently a flow of wastewater across the State Highway. The burst
main has caused an overflow and will continue to do so until repaired.
The Incident Response team is being formed to manage the response. A further update will be
provided approximately 10:30.
Kind regards
Glenis
Glenis Bruin – Incident Coordinator
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Customer Experience Team
Ph 04 912 4470
Mob 021 346 438
Private Bag 39804, Wellington Mail Centre 5045
Level 4, IBM House, 25 Victoria Street, Petone, Lower Hutt
www.wellingtonwater.co.nz
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SITREP – Paremata Wastewater Riser
EMT Activated 11.00 AM Saturday 17/7
Incident Coordinator: Garry Butler
Network Controller: Gary O’Meara
Comms: Vanessa MacFarlane / Grace Christinson & Julie Alexander (Senior GWRC/PCC/Ngati
Toa)
Intelligence: Sam Lister (support Dylan Hopkins, Glenis Bruin)
Planning: Sam Lister / Steve Hutchison
Ops/Logistics: Sean de Roo / Paul Davison (Paremata) Grant Ngarewa (COG region)
Health and Safety: Rob Mackie / Luke Taylor
Environment: Paul Gardiner
Saturday 17/7 10.00 am
BURST WASTEWATER RISING MAIN
Response: Level 4
Response Lead: Sam Lister
Supported by: Service Delivery Team
The 525mm diameter Wastewater Rising Main on SH 1 has ruptured. At this stage we are planning
to do an urgent repair. There is currently a flow of wastewater across the State Highway. The burst
main has caused an overflow and will continue to do so until repaired.
The Incident Response team is being formed to manage the response. A further update will be
provided approximately 10:30.
Saturday 17/7 10.30 am
EMT Activated
Saturday 17/7 11.30 am
UPDATE 1 – 11:30
The Incident Response Team has met, and work is underway to excavate and repair the broken
pipe. A media release is going out now and is shown in its entirety below:
Wastewater main burst on State Highway 1 in Paremata.
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Public are being asked to expect delays on State Highway 1 (SH1) in Paremata and avoid swimming
in the Paremata harbour due to a burst wastewater main between the Aotea turnoff and
Plimmerton, 200 meters north of Aotea lagoon.
Wellington Water was called out to a burst wastewater main on SH1 around 8am today.
“This has caused wastewater to overflow across SH1 and into the Paremata harbour. State Highway
1 is currently down to one lane north bound and people should expect delays,” says Sam Lister,
Wellington Water’s Manager Customer Planning.
“There are nine wastewater tanker trucks on site which is helping to reduce the overflow on SH1 and
crews are planning to do an urgent repair.”
Works are expected to go into late evening tonight. A no swimming notice will be put up onsite near
the harbour entrance which will remain in place for 48 hours after the overflow stops.
“With the heavy rainfall likely to cause more overflows, we’re also asking residents to conserve
water as much as possible.
“We’d like to thank the public for their patience as we work to repair the burst.”
Saturday 17/7 12.00 noon
EMT Current status -
A wastewater pipe has fractured in the vicinity of SH1 Aotea Lagoon/ Paramata. There are SH 1
traffic disruptions as a result and wastewater is discharging into the harbour and neighbouring
surface areas including a school playground (unoccupied). Heavy rain continues and forecast to
ease this evening. Situation being monitored for any further escalation.
Traffic – Traffic management is in place with northbound SH 1 down to 1 lane. Liaison
implemented with NZTA (Paul D)
Comms – Comms has been undertaken including media release re status (Vanessa /Julie)
• Board/SLT
• GWRC
• PCC
• NZTA
• Ngati Toa
• RNZ, TV
• FB channel
Planning (Sam / Sean)
• Pumps being controlled to minimise effects
• Sucker trucks mobilised
• Repair is contingent on supply of parts being sourced from Wanganui. Delivery unknown.
GP Friel on site and advising
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• Alternative wastewater flow path being investigated
• The work may take 24 hours to effect, further resources being investigated
• H&S issues being monitored
Environment / Public Safety (Nick)
• Signage is being placed around the affected area and harbour (Alistair)
• Keep out of flooded areas to be emphasised
Saturday 17/7 3.30 pm
UPDATE 2
Work continues on the burst wastewater rising main. Contractors are on site and sucker trucks are
operating to assist in reducing the overflow. Below is the media release sent out at 15:30 this
afternoon.
Further investigation by Wellington Water around the burst wastewater main on SH1 in Paremata
has found that the incident has also caused a wastewater manhole to overflow wastewater on to
Station Road, Paremata Crescent and on some areas near the entrance of the Paremata Primary
School grounds.
We are asking pedestrians to take extra care and avoid these areas.
We have a team on the ground who have cordoned off these areas with cones and people on site
with signage. We also have suction trucks working in this area to control flows.
ENDS
The Incident team will be meeting again approximately 16:30 and we will provide a full update
following that meeting.
Saturday 17/7 5.30 pm
UPDATE 3
Our crews have been onsite all day working to fix the burst rising main on SH1. This work has been
challenging due to the continued heavy rainfall. We are currently undertaking temporary works to
direct the wastewater flow from the main through the Cross Harbour Pipeline as an alternative path
to the treatment plant outfall.
Our teams will be working through the night to carry out a temporary repair of the rising main with
the aim to implement the permanent repair tomorrow once the rain has eased.
Traffic is very congested currently in the affected area of SH1 (between the Aotea turnoff and
Plimmerton, 200 meters north of Aotea lagoon).
We’re asking people to find alternative routes or delay travelling if possible.
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Signs have been placed to warn people to avoid swimming in the Porirua Harbour and Social Media
has warnings for pedestrians to avoid any local areas with surface flooding as this could contain
some wastewater overflow.
We’d like to thank the public for their continued patience while we work to fix this issue.
Kia ora Board,
As reported earlier, our teams have been dealing with a burst waste water pipe at Paremata – see
the attached media release on the latest update. We have had two media enquiries (Newstalk ZB
and Stuff) since issuing these updates but we’re getting pick up on all the main media outlets (NZ
Herald, Stuff, Newshub, and Newstalk ZB) with these outlets just reporting what’s being provided
from our statements. We’ve also been providing the public with regular updates on our social
media channels and our website.
The weather event has put considerable pressure on our crews across the region, with many calls
coming in that we have needed to respond to. For example, we have had 88 jobs within the Hutt
City area, 89 within Wellington City, and around 30 within Porirua City. The jobs relate to flooding
and waste water bursts.
In addition to the event in Paremata, our teams are working on another significant event in
Petone, where the pressure culvert has burst causing significant flooding in some surrounding
streets. The flooding is stable at the moment but we are monitoring it closely.
We are also monitoring the Hutt River levels as these are predicted to increase. A higher than
usual tide is also predicted for later tonight. If these eventuate, the risk of flooding increases.
We are actively monitoring the health and safety of our people, and drawing on resources across
our contractor panel to supplement our crews.
Our teams are doing a great job in difficult conditions. It’s been a very busy 24 hours, with
potentially more impacts from the weather to come. I’ll keep you updated as needed.
Sunday 18/7 7.47 am
Paremata
Situation update, Over pumping at Station Road with one pump was insufficient due to
manage flow due to the high wet weather flow. We trialed turning off both PS6a and PS6b and
with both pumps off this did not reduce the flow into the failed riser main confirming flow is
entering the risermain through other sources. Additional pumps are being sourced for
tomorrow morning. GP Friel have gone home to rest to carry out repair tomorrow morning.
Utilities staff have done their hours and fresh hands lined up for morning. PS6a wil remain on
overnight along with temporary over pumping to constructed overflow and suction trucks to
continue flow management.
Sunday 18/7 10.44 AM
Paremata & Wider Flooding
EMT Current status - A wastewater pipe fractured in the vicinity of SH1 Aotea Lagoon/ Paremata
17/7. There are SH 1 traffic disruptions with one lane closed and wastewater is discharging into
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the harbour and a school playground (unoccupied). Rain has stopped but may be more this
evening
Attempts during Saturday 17/7 to isolate the break were unsuccessful although flow was
minimised through diverting some of the flow to an emergency pipeline across the harbour plus
pumping
Efforts continue this morning to stop the flow with extra pumps, sucker trucks so that repair can
be enabled
Traffic – Traffic management is in place with northbound SH 1 down to 1 lane. Liaison
implemented with NZTA (Paul D)
Comms – Ongoing comms implemented (Vanessa /Grace/ Julie/Glenis)
• Board/SLT
• GWRC
• PCC
• RPH
• NZTA
• Ngati Toa
• Media
• FB channel
Planning (Sam / Sean)
• Pumps being controlled to minimise effects
• Further pumps being mobilised to further cut flow
• Sucker trucks mobilised
• Repair parts are on site. GP Friel on standby to commence repair
• The work may take further 12 hours to effect
• H&S issues being emphasised and monitored (Rob M)
• School property owner to be notified of contamination of grounds
Environment / Public Safety (Nick)
• Signage has been placed around the affected area and harbour (Alistair)
• Keep out of flooded areas
Wider Network
A significant number of properties across the network have been flooded.
Confirmed hot spots are Ava St which was significantly flooded but has subsequently drained, and
property in Holly Grove.
COG Hub to review customer calls (100 + across the region yesterday), establish contact with
councils to identify areas of concern and determine extent and establish priorities forcontact/
response/recovery. (Grant/Glenis)
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Sunday 18/7 11.10 am
UPDATE 4
We’ve had sucker trucks on site helping to reduce the overflow to Porirua Harbour and keep
contaminated water away from Paremata school. Overnight they have managed to keep up with the
flow with less rain and stormwater infiltration into the network.
Work continued overnight on diverting the wastewater flow through an emergency line underneath
the harbour. This line was successfully opened, and some wastewater diverted through it to relieve
the pressure on the broken main. As the main could not be fully isolated repair work was unable to
be completed. Additional pumps are being installed to assist with the diversion of the flow.
This work has been challenging due to heavy rainfall and high levels of stormwater infiltration into
the wastewater network.
Today:
Contractors are on site again today working towards an urgent repair on the Rising Main.
This involves digging a trench in the SH1 median strip, removing the damaged section and replacing
it with a new pipe.
As we need the pipe to be drained when we do this, the timeframe is dependent on the weather and
the amount of infiltration we experience due to rainfall.
We hope to complete the permanent repair completed today before the rain starts again later
tonight.
Works are expected to go into late evening tonight. A no swimming notice has been put up onsite
near the harbour entrance which will remain in place for 48 hours after the overflow stops.
We’re also asking residents in Whitby, Paremata, Plimmerton, Pukerua Bay, and in the northern
parts of Papakowhai to minimise water use as much as possible.
To work on the repair, State Highway 1 has been reduced to one lane north bound (between the
Aotea turnoff and Plimmerton, 200 meters north of Aotea intersection).
We’re asking people to find alternative routes or delay travelling if possible.
The Incident Response Team is meeting regularly and I will be sending out updates as the work
progresses today.
Kia ora Board,
As a recap, our teams have been dealing with a burst wastewater pipe at Paremata. This caused
wastewater to overflow alongside and onto SH1 and into the Porirua harbour. To work on the
repair, State Highway 1 was reduced to one lane north bound.
Overnight we’ve had four sucker trucks on site helping to reduce the overflow to Porirua harbour
and keep contaminated water away from Paremata school. They have managed to keep up with
the flow with less rain and stormwater infiltration into the network.
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Work was also continued on diverting the wastewater flow through an emergency line
underneath the harbour. This line was successfully opened, and some wastewater diverted
through it to relieve the pressure on the broken main.
However, as the main could not be fully isolated repair work was not completed. This work will
continue today. This involves digging a trench in the SH1 median strip, removing the damaged
section and replacing it with a new pipe.
As we need the pipe to be drained when we do this, the timeframe is dependent on the weather
and the amount of infiltration we experience due to rainfall. We hope to complete the repair
before the rain starts again.
We’ve had had two media enquiries (Newstalk ZB and Stuff) since issuing the updates yesterday
but we’re getting pick up on all the main media outlets (NZ Herald, Stuff, Newshub, and Newstalk
ZB) with these outlets just reporting what’s being provided from our statements so far. We’ve also
been providing the public with regular updates on our social media channels and our website.
We are working closely with senior managers at PCC and GWRC (environmental regulator), as
well as Waka Kotahi to coordinate messaging for transport and keeping Regional Public Health
informed. I reached out to Ngati Toa yesterday, and will do so again today.
We are still under pressure across other parts of the network as a result of yesterday’s weather
event, but the Paremata burst is the one that is causing me the most concern.
Sunday 18/7 13.15
Paremata UPDATE 5
We currently have 4 pumps on site at Station Road pumping to the stormwater over flow point,
Station village pump station pumping through the Cross Harbour Pipeline as well as 12 Wastewater
tanker trucks carting from upstream to Porirua City Centre pump stations. This has enabled us to
control the flow of wastewater at the burst site sufficiently to commence repairs.
We are now starting on the excavation work in preparation for the repair of the pipe.
Further updates will be provided as the work progresses during the afternoon and early evening.
Sunday 18/7 3.45 pm
Paremata UPDATE 6
We’ve made good progress on the repair to the wastewater pipe in Paremata with the pipe
excavated and the new pipe being installed now.
The work involves digging a trench in the SH1 median strip, removing the damaged section, and
replacing it with a new pipe, then infilling and cleaning up the area ready for north lane of SH1 to be
reopened.
While we’re expecting to be able to complete the repair today, we’re going to need to revisit the site
to complete some tidy up work. This will be carried out in the next week and during off peak traffic.
A further update will be provided approximately 18:30 this evening.
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Thank you for your patience and we apologise for the inconvenience.
Kia ora,
Latest update, with good news.
We’ve made good progress on the repair to the wastewater pipe in Paremata with the pipe
excavated and the new pipe being installed now. The work involves digging a trench in the SH1
median strip, removing the damaged section, and replacing it with a new pipe, then infilling and
cleaning up the area ready for North lane of SH1 to be reopened.
While we’re expecting to be able to complete the repair today, because of the waterlogged
material, we’re going to need to revisit the site tomorrow to complete the infill and final clean up.
We’ve had had no media enquiries today, although Stuff have published a story using our social
media updates – link here:
https://www.stuff.co.nz/dominion-
post/news/wellington/300360475/burst-water-main-at-paremata-north-of-wellington-spills-
wastewater-over-highway We have a media release ready to go – see attachment. We’ve also been providing the public with
regular updates on our social media channels and our website.
We are watching the health and safety of our crews, who are good spirits this afternoon – with an
end almost in sight and drier working conditions.
We’ve also opened up a dialogue with Ngati Toa.
The weather event continues to put considerable pressure on our crews across the region, and
customers will be experiencing delays for lower priority jobs.
We’ve also had reports that there has been storm damage at the Omāroro Reservoir site, with
some erosion on the earth works face and water damage to vehicles from the stream bursting it’s
banks. We are letting WCC know about this.
All in all a very busy weekend for the company, but a sterling effort from everyone involved and
huge commitment from our staff and wider whanau. Ka pai!
Sunday 18/7 5.31 pm
Metservice in touch and advised that a heavy band of rain coming very soon, could be up to
15mm an hour for a couple of hours, temperature wil drop with a southerly
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Sunday 18/7 9.15 pm
Paremata
EMT agreed actions and operating status for 525 risermain overnight
Bora Cres and Aotea lagoon pump stations to remain operational
PS6a Station Road to remain pumping across the harbour pipeline
PS6b one pump operating only to minimise discharge to Porirua harbour and minimise operating
pressure
Temporary over pumping to stormwater and Station Road will remain in place to deal with
additional flows
Single lane traffic management remains in place over night
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EMT agree one maintain one pump in operation at PS6b as preferred option to minimise
discharge
Operating pressure of the 525 reduced to risk further AC failure
EMT agreed actions and operating status for 525 risermain overnight
Bora Cres and Aotea lagoon pump stations to remain operational
PS6a Station Road to remain pumping across the harbour pipeline
PS6b one pump operating only to minimise discharge to Porirua harbour and minimise operating
pressure
Temporary over pumping to stormwater and Station Road will remain in place to deal with
additional flows
Single lane traffic management remains in place over night
EMT agree one maintain one pump in operation at PS6b as preferred option to minimise
discharge
Operating pressure of the 525 reduced to risk further AC failure
Kia ora Board,
Unfortunately, the latest update is that the pipe replacement has not gone as well as expected. A
photo from the site shows that there is severe corrosion at the top of the pipe. Because of the
instability, it has not been possible to complete the repair.
The focus is on stabilising the situation as best we can overnight, and we will regroup in the
morning. Our aim is to minimise the overflow into the harbour, we will have people on site
overnight to monitor and sucker trucks present. Our crews are fatigued and we are resting them.
Apologies for raising hopes earlier.
Monday 19/7 00.21 am
Paremata
Due to rainfall, the volume of sewage coming in from 6B was too much and whilst we do not
have the all the big sucker trucks operating there was a risk to overwhelm and flood the school.
The emergency standby sucker trucks would in be in a position to cope. After discussion with
Paul W, they have turned on all the diesel pumps, i.e. pumping to stormwater again and also
turned on the 2nd pump at 6B. The leak on the main pipeline has not increased as a result of
turning on the 2nd pump. This has been status quo for circa the past half-hour. The plan for now
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to leave both pumps pumping from station 6B. The risk of stop-starting pumps too much would
be concern. Sean wil check with Paul re what auto mode of pump station would do. In summary
therefore status at moment: 2 pumps pumping at Station 6B. All diesel pumps operational and
pumping excess to stromwater.
Monday 19/7 00.43 am
Paremata
The rain situation in Porirua has resulted in most of the significant pump stations overflowing
such as city centre, Rukutane at present. We wil keep both pumps operating at station 6B and
this status quo wil remain for the rest of night whilst watching the main pipeline status. Once the
wet wel levels at station 6A start dropping we wil turn off the diesel pumps to stop the
discharges to stormwater. Joe wil take a note of what time that wil be.
Monday 19/7 9.12 AM
Paremata
Two pumps running at PS6b currently managing flows, Leakage has been confirmed as beyond
new section of pipe at both ends Planning to repair using clamp fittings to avoid further
shutdown and discharge.
Monday 19/7 10.00 AM
EMT - Paremata Wastewater Incident
Current state on site – Setting up for another shutdown to remove the joint from yesterday to
repair. Stainless steel wrap on either side to seal and support – leak coming through top of the
pipe. Achieved without shutdown. Next step to turn the pumps back on to see how the pipe fairs.
One of two pump stations in service – 6B is in service 6A is not.
Not back in full service as 6A is valved off from main – when all pumps are back on risk that the
repair won’t stand up against high pressure.
Last night – another rain event and 6A nearly overflowed into the school, 6B nearly overflowed
into the roundabout. This informed decision to turn on second pump. System can’t handle heavy
rain.
Current discharges to environment – discharging last night, flows in network dropped off
overnight. Flows are being managed with two pumps running at pump station 6B. Material has
discharged into harbour overnight with rain – now pumping through cross harbour main with
flows levelling out.
Sewerage is getting to Titahi Bay – severity of flow unknown. If the flow is going through Harbour
line it is excessing somewhere unknown. Need to re-look at configuration to gain understanding
of what is happening/going wrong.
Plan is road open by 3pm this afternoon – contingency planning for future occurrence needed.
Decision on how many pumps we allow to operate from 6B – live with some overflow to avoid
high pressure risk.
Short term plan – run with two pumps to keep adequate flow going. Will cope with dry weather
not with rainfall. If we get rainfall we allow to overflow and assist with diesel pumps. Dry
weather we will cope with no discharges to environment.
Water screening: beyond 24 hours – get into contingency of setting up additional pumping over
land would mitigate water screening issue. No short-term mitigation within the next 24 hours.
No visible signs of rags on beaches thus far.
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Steve – go across harbour to ease pressure on pump station 6B in the short term. Want to verify
where the flow is getting to. Known contamination from significant overflows – based on
observations it is most likely getting through. Key objective – working to minimise wastewater
contamination into the harbour.
Dye testing on outgoing tide – to find possible leaks.
This morning – getting sucker trucks organised, isolating pump station. Going over to isolate
station 6B – sucker trucks at 6B and station road utilising diesel pumps. Close outlet valves on 6B
to reduce flow – then work can go ahead with moving the connection.
Waiting on 2 bolts to come in – should be bolted up in next 30 mins. Replacing bolts from earlier
repair.
Key commissioning steps – in service with two pumps running in 6B. First identify if flow is going
across harbour before deciding whether to configure. Leave harbour link on until flow is verified.
6B is operating as designed at the moment.
If we get rainfall, we are going to discharge wastewater into the harbour.
Objectives for the morning – repair almost complete. Once repair is done – if it is holding up, we
will knock off sucker trucks. Continue pumping across harbour and explore what is happening with
flow. Unless there is wet weather – the flows are contained.
Main objective – verify what is happening with cross harbour link. Environmental side of things is
in control unless high rainfall. If repair goes to plan the highway will be open by 3pm. Full steam
on contingency plans.
Key message – It is a temporary repair – delicate situation and we expect it to fail again.
Colin - Bring in a whole new contractor for the renewal of the pipe.
Proactive comms – stressing that it is an ongoing issue. Dealing with flows for today but operating
on limited capacity. Behave as though it will break – extra precaution. Pipe is fragile – we are
working on additional contingency measure. We are doing the least environmental impact. Ngati
toa agreement.
The orca will come back into conversation – managing risk to the orca. Huge public interest. Paul
Gardiner to contact DOC about this issue – should assume that the water has been contaminated
for the last 48 hours.
The school has been notified – signs are up around the school about contamination risk. School
will be reimbursed for tidy up. Buildings are safe.
Sam Lister to document configuration – with a contingency that we will operate pumps if needs
arise.
State of the pipe – struggling to hold onto existing pipe because of the condition. Pipeline is 2km.
Assume that majority of the pipeline will be in poor condition. 2012 LTP – this had been raised as
a critical issue.
Not being looked at as a renewal – it is an upgrade in the PCC network upgrade programme.
Contingency plan - get some more fittings and pipe in the case of another burst short term for
smaller repairs ASAP – get the long-term upgrade in plan asap – fast-track CAPEX.
Fittings must be custom made and delivered – there may be a week delay. Ordering 2 sets of
fittings now.
Sampling continuing once a day at 5 sites – Nick Hewer-Hewitt in charge of this.
Clean up of lagoons – several tide cycles to get wastewater out. Need support in that space –
connect water. Increase signage.
Kia ora Board,
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This morning’s update is that the pipe has been repaired, but it is very fragile and there is a high
chance it will burst again. The discharge to harbour has been stemmed for now, but could occur
again either as a result of heavy rain and/or a further burst.
We have had some media interest this morning looking for an update – see our response
attached.
We are prepping a media and engagement strategy on the assumption there will be a burst /
further discharge.
We have turned our minds to implementing a two phased approach that recognises the condition
of the pipe and the risks we are managing – a more reliable interim solution and a more
permanent and longer-lasting solution – and options for accelerating both approaches.
Colin is arranging to meet with Ngati Toa, hopefully first thing tomorrow morning. As well as the
cultural harm that has occurred from the discharge itself, Ngati Toa have had a long term
opposition to the use of the old cross harbour pipeline that we have pressed into service to help
stem the discharge. We consider that using the old pipeline in this emergency has given us a
better environmental outcome overall, and the aim is to talk this through with them.
We will also reach out to DOC today to liaise in regards the well-being of the baby orca, Toa, who
is being cared for in a large holding pool, and the volunteers who are looking after him. The
holding pool is being refreshed using sea water from the harbour. We understand the orca is
being located back into the marine environment today. Whilst peripheral, we are keen to manage
any associated risk between the Paremata burst and anything to do with the orca and the
volunteers, as this is likely to have significant media interest.
Monday 19/7 12.48 PM
Paremata
EMT Current Emergency State
-
Pipe repair is complete with extra stainless steel reinforcing banding at each end,
backfilling has commenced
-
There is no (current) dry weather wastewater overflow to the environment
-
The pipe is in a fragile state, there is high risk of another fracture at any time and
therefore discharge of wastewater to the environment
-
The proposed pump configuration will ensure reduced pressure in the pipe Flow through
the cross harbour pipeline will be continued. Further periods of heavy rainfall will
necessitate pumping wastewater to stormwater. This arrangement to be documented
(Sam)
-
The closed lane on SH1 will be able to be re-opened before peak time this afternoon
-
A LAWA warning on sea water quality in the area to be reviewed and updated
(Steve/Nick)
-
Environmental expert to be consulted regarding pond contamination (Gary C)
-
School is aware of the issue and will be assisted with the clean-up (Sean)
Short Term Ops Contingency Plans
-
Further repair parts are to be ordered from Australia, lead time approximately 1 week
(Paul D)
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-
Some parts are on site to effect makeshift repair in the interim (Paul D)
-
An ops action plan is to be prepared with H&S considerations (Sam/Sean/Rob M)
Medium term (weeks) plans to Improve Resilience (GC)
-
Investigation into laying a new section of PE pipe to be put into service in parallel with the
fragile sections (Gary C/Ian)
Long term plans (months/year)
-
Acceleration and planning and pricing for longer term asset renewal/replacement (Gary
C/Ian)
Communications
-
Key communications under preparation to all stakeholders / media / public
(Julie/Vanessa)
Monday 19/7 15.05
Paremata UPDATE 7
We have now completed the repair and backfilled the excavation, which has contained the discharge
of wastewater.
It has been identified that the condition of the AC main is in very poor condition and likely to fail at
some stage in the near future.
To manage this risk, we are arranging for specialised repair fittings and pipe to be available on site.
Temporary mobile pumps have been established in Station Road to manage any high wet weather
overflows that may occur.
The two north bound lanes on State Highway 1 will be open this afternoon by 3:30pm.
Monday 19/7 5.15 PM
Paremata
EMT Current Emergency State
-
Pipe repair is complete with extra stainless steel reinforcing banding at each end,
backfilling completed
-
There is no (current) dry weather wastewater overflow to the environment
-
The pipe is in a fragile state, there is high risk of another fracture at any time and
therefore discharge of wastewater to the environment
-
Some unexpected flow behaviour has been observed and is to be further investigated
(Paul W)
-
Further periods of heavy rainfall will necessitate pumping wastewater to stormwater.
-
The closed lane on SH1 has been re-opened
-
A LAWA warning on sea water quality in the area to be reviewed and updated
(Steve/Nick)
-
Environmental expert to be consulted regarding pond contamination (Gary C)
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-
Assistance has been provided to the school for its clean-up
Short Term Ops Contingency Plans
-
Further spare repair parts are to be ordered from Australia, lead time approximately 1
week (Paul D)
-
Some parts are on site to effect makeshift repair in the interim (Paul D)
-
An ops action plan is to be prepared with H&S considerations (Sam/Sean/Rob M)
EMT / Ops / PERT / Capital Projects
-
EMT has stood down as impacts have been eliminated to near normal levels of
service. EMT will respond to any future major events
-
Ops now lead incident management including establishing contingency plans and
arrangements (Sam L)
-
EMT Incident Coordinator has activated PERT to review medium and long strategies to
improve resilience and levels of service(customer/environment)
-
Capital Projects is planning for resilience and service level improvements
Communications
-
Key communications undertaken and ongoing to all stakeholders / media / public
(Julie/Vanessa)
------------------------------------------------------------------------------------------------------
Tuesday 20/7 3.48 pm
Paremata UPDATE 8
In taking pressure off the Paremata rising main, we recommissioned the cross-harbour pipeline
from Station Road to Onepoto. In doing this, a blockage occurred on the walking track (Onepoto
side), resulting in overflow into the Harbour for under two hours. In response, the pumps were
turned off and the flow diverted back to the rising main.
This means that the rising main continues to operate under stress and we are monitoring the
situation. We have ordered additional fittings to enable further repairs.
We will also work towards making the cross-harbour pipeline serviceable by pressure testing with
potable water, as a viable alternative to the Paremata rising main should it be needed.
The walking track has been temporarily closed.
Tuesday 20/7
EMT Incident Coordinator recommends that PERT also provide focus on the wider regional flooding
events recovery
Paul Gardiner contacts DOC re the Orca in Plimmerton advising of the situation with water quality to
enable their decision making
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Wednesday 21/7 5.45 pm
Paremata UPDATE 9
The clean-up of the walking track has been completed today. Contractors will continue working on
the walking track and Station Road tomorrow to enable us to conduct a CCTV investigation of the
Cross-Harbour Pipeline. The walking track will be reopened to the public once contractors have
finished their machine works.
Arrangements have been made to transition the current portable pump set up at Station Road to
align with the Cross-Harbour Pipeline being offline and its effect on the existing pump stations. This
will be done before the school holidays end this weekend to minimise impact on the Paremata
School. The school has a side entrance off Station Road.
The next update will be provided once pressurised testing has been completed.
Thursday 22/7 5pm
EMT Reactivated
Paremata UPDATE 10
• Pipe burst at same location
• Wastewater coming out of area of original break – wastewater going through culvert and some
spillage over SH1.
• 2 pumps at 6B and 1 pump 6A (Station Rd) are running so some flow is still going through the
rising main. The remainder is being pumped using the temporary pumps at Station St to the
harbour.
• GP Friel ready to commence work tomorrow, WWL to do prep to enable work to start as early as
possible. Pipe available at Pomare - 6m length, Clamps will have to reused.
• Sucker trucks on their way.
• Work to put cross harbour back online
• The decision was made not to start the actual repair until Friday morning. This was due the
weather (heavy rain), night work involved, health and safety of the team involved and time need
to set up the sites. TM to be set up ready for a Friday morning start.
Plan -
The photo below documents the plan and responsibilities for the evening and overnight.
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Following is the agreement around the use of the cross harbour ww main….
-----Original Message-----
From: Colin Crampton
<[email address]>
Sent: Tuesday, 20 July 2021 5:50 pm
To: Helmut Modlik
<[email address]>
Cc: Wendy Walker
<[email address]>; Ian McSherry
<[email address]>; Paul Gardine
r <[email address]>
Subject: Paremata wastewater pressure main.
Kia Ora Helmut, thanks for meeting with Wendy and I this morning.
As discussed the Asbestos Cement pressure main running from the Paremata roundabout south to
the off ramp at Porirua is in a very poor state. This led to a rupture of the pipe on Saturday 17th of
July and an overflow of wastewater into the Porirua Harbour during the balance of Saturday, Sunday
and part of Monday. The total amount of wastewater to overflow was limited by the use of sucker
trucks and the recommissioning of the old wastewater pressure main under the Porirua harbour
which tracks back along the western side of the Onepoto arm to the rowing club in Titahi Bay. A
repair has been completed but it is expected further ruptures of this pipe are likely to occur.
There are two circumstances to account for should another failure occur; as follows:
1. During dry weather, in which case we should be aiming for no wastewater overflow into the
harbour using a combination of sucker trucks; the cross harbour pipeline and an expeditious repair;
and
2. During wet weather, mitigate the size of the overflow into the harbour using the same tools
above.
We will now urgently investigate a permanent renewal and upgrade of this pipeline using a design
philosophy that does not rely on spilling into the harbour as the contingency plan. This work is likely
to take 12 months to 18 months to complete.
So our request of Ngati Toa Rangitira is to recommission the cross harbour pipeline to be used as
described above so as to avoid the discharge of wastewater into the Porirua harbour as far as possible
in any subsequent failure.
To be clear we would use the cross harbour pipeline, as follows:
1. In an emergency should a break occur;
2. As a supplement to operations when we have checked it is water tight and durable; and
3. We would decommission its use once the permanent solution has been effected.
At all times we use the Cross harbour pipeline we will record the times and advise you.
Thank you for meeting with us this morning and discussing this predicament.
Colin
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Comms that went out to the media
Attribute to Steve Hutchison Chief Advisor Wastewater, Wellington Water
We are currently responding to a burst wastewater main on State Highway
One, northbound, between the Aotea turnoff and Paremata.
Traffic management is in place and we encourage members of the public to
avoid the area if possible.
This pipeline previously burst last Saturday and a repair was carried out on
Sunday evening.
Despite the repair, our investigations showed the pipeline was in a fragile
condition, and this evening’s heavy rainfall has caused a further failure.
Some wastewater is overflowing into the harbour and work is underway to
minimise this overflow.
Our crews will be preparing throughout the night to undertake a further
repair in the morning.
We advise members of the public to avoid contact with coastal water in the
area.
Thursday 22/7 10pm
Paremata UPDATE 11
• Two breaks one on each side of the previous repair
• Cross harbour pipeline being commissioned – will turn on the pumps and see if can pump (2
hours to commission)
• 3 sucker trucks on site
• Temp pumps turned off
o Flows low
o Currently not discharging into the harbour
• Traffic management has been set up
• GP Friel on site Friday morning – lane to be closed to bring digger on at 6:30am
• Monitor set up – Luke and Silver linings
Friday 23/7 8am
Paremata UPDATE 12
• Cross harbour pipeline was turned on and a break occurred. This resulted in a small
discharge by Onepoto.
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• From 10pm there was no discharge to the environment except from the cross harbour
pipeline break.
• Any discharge from the actual break is to the swale and doesn’t reach SH1 – leakage is less
than previous break.
• Two breaks one on each side of the previous repair
• GP Friel is on site, the 6B pumps are still running, will be turned off when the pipe is
uncovered to assess the extent of the failure.
• Questioned whether this was the best time to start work, ie should we wait until lower flows
overnight. It was decided starting was the best option as it was daylight, full complement of
staff and we need to manage the risk of the pipe failing further.
• Managing the overflow through sucker trucks but will be still discharging to the harbour at a
location that flushes well.
• Consider whether more condition information can be gained while the pumps are off - SR
• The ranger responsible for the orca has visited the site but has no concerns.
• Ensure we get as-built info - Francis has a schematic of the values and cross harbour pipeline
connection. Need to make sure this information is fed back to DPS.
Plan B
• Determine how much pipe would be needed if a larger repair is needed?
• Determine if the pipe is available.
• Check to see if we can reinstate the cross harbour pipeline.
Plan C
• polyethylene pipe on site in case we need an overland pipe (not yet actioned).
Risk of comms escalation has been identified.
Friday 23/7 11am
Paremata UPDATE 13
• 9am sucker trucks operational – 15 trucks
• Discharging to harbour
• First leak split on collar (12 to 3o’clock) – 4m south of previous leak looks like a blow out
• Ready to expose second leak - Second leak likely to be similar distance from repair – more of
a worry.
• Marked out xhp for repair
• OF form for xhp leak last night
• Pot holed further south to see if any PE – AC. Need to look north GIS shows PE (same as
asbuilt)
• Traffic – moving alright
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• More wiser in an hour
• Ian to talk to PCC Roading
• Check signage for xhp break. – Sam
Friday 23/7 1:30pm
Paremata UPDATE 14
• Exposed break points – northern leak not obvious. Putting clamp over collar and turn on 6A
pump to put flow though the line to find leak
• 6 in pump to harbour
• Harbour link – now what we need to do. Need to get fittings – Monday.
• 4-6 hours next three hours
• Traffic major problem
• Logging all overflows – these will be provided early next week
• Durafit clamp getting installed now – within hour can make a decision on whether it is
effective or not. Will need to charge up the other pumps.
• Check with capital journeys
• Job coming in from Paremata School – lowest point on gravity network.
• Call on installation
• Trying confirm where HDPE starts – not far from site of the break (10M).
• Chris and Amber on site – plan in place for 6A, 6B not plans for Bora, Tweed St. C&A will
prepare a plan.
• We will try to get off site as soon as possible due to traffic, need to liaise with capital
journeys around requirements around the site.
• Rahui – being placed from tomorrow by Ngati Toa at the Onepoto site
• Sampling sites being extended.
Friday 23/7 3pm
Paremata UPDATE 13
• Have confirmed with capital journeys that equipment can be left on site. Hole needs to
backfill.
• Won’t pursue northern leak
• Coupler compressed inside joint
• A photo of the crew in the trench raised concerns around trench stability. It has been
confirmed that the trench does not need shielding. The hole is approx. 1.4m dept and the
wall are solid and well compacted and not at risk of collapse.
• One lane closed for a section 50km speed limit
• Sucker trucks current there till 7 -8 pm one’s on last night will come back
• Keep pumping through then if major failure.
• Plan for tomorrow – need to check after 5pm. Likely to be as per Thursday night.
• Resources - 10pm – run out of resource – monitoring manholes, Valitha and Paul W to look
at resourcing
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Friday 23/7 5pm
Paremata UPDATE 14
• Leakage from clamp so needing to depressurise and try and fix coupling, crushed side
holding other side leaking. Still trying to get a better seal, keeping pipe live
• Some back up of traffic – no worse than a normal Friday
• Sucker trucks off site from between 7 and 8.
• If don’t work, going to have to run with overflow. South should hold. North is slowly getting
worse.
• Need to find out if work can continue tomorrow – ie if crews are available.
• Ensuring staff are available and briefed for overnight monitoring.
Friday 23/7 7:30pm
Paremata UPDATE 15
• The repair was unsuccessful the pipe is too fragile to maintain a solid connection (south side
of the south repair). The pipe is still leaking but less that it was last night. Several
connection options were tried. Have dug a swale to contain spill.
• Overnight we will continue to pump flow through the pipe (100L/s), use sucker trucks and
temporary pumps to discharge through the SW culvert if needed (currently not being used).
Sites will be monitoring. Consider sucking off SH1 if the failure increases.
• Day crew are vacating the site.
• We will need to get crews on site to replace pipe Sat morning (or sat night) although this
cannot be the same crew as today due to fatigue.
• Reduced crew of sucker trucks (3) from now.
• Consider replacing with CLS across main failure and then provide internal pipe for integrity
and something for the joint to bind to. Patches will provide the internal integrity. New
section from southern and northern repairs approx. 12m.
• Confirm there are patches in Levin (2).
• Tartners will then help GP Friel with installation, Sean to get resource and material
confirmation.
• It was agreed that we need to get have contractor present on site tomorrows
Saturday 24/7 10am
Paremata UPDATE 16
• Maf relieved by Royce
• Rob relieved by Ben (PS management)
• PS all operated fine overnight – a bit more flow than normal (Sat morning usual)
• No overflows to harbour
• Rahui – moved to 1pm
• Plan
o Attempt permanent repair
o Same sucker trucks (13-15)
21-108
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o 12m length CLS being delivered (James Bulk Water team helping Hammonds with
loading) with 2 step couplers,
o Internal pressure patches getting flown down from Auckland will need to be picked
up at the airport with trailer (Sean)
o Tartners have the gear and will be on site
o GP Friel reduced staff (new team pulled off another job)
o Rambo’s on call for Sun morning if needed for tidy.
o Technique used before.
o CLS connected using pressure patches, step couplers, to AC – still a risk.
o Timeframes – likely to take till 8pm for backfill.
• Contingency – encasing in concrete – high risk could crush pipe, idea evolved could grout in
repair and box in repair.
• Need to fully replace pipe ASAP
• Catch up at 2pm.
Plan B –
• Run as per previous 2 nights. Will need to monitor.
• Shifts need to be set up for Saturday night, Sunday day and Sunday night. Starting 8pm.
Refreshments
Approx 30 people lunch around 1, dinner around 6pm
Comms
• May need someone near the railway bridge if discharge due to boating activity
Longer term response/issues
• We don’t know condition of full length risk very high
• AC starts at repair and goes for 1km to nearest MH.
• Have tried 3 different types of repair and have struggles, have to think outside the square.
• Need to set up a separate team to come up with the med term repair
• Low level of cover but a risk that we cause damage by tracking over it.
• Water hammer is a risk of the substandard AC – what can we do to mitigate this? Paul W
• Wang clamps ideal for first choice of material
Saturday 24/7 2pm
Paremata UPDATE 16
• Could not get connections down from Auckland. Now being transported by road and being
picked up in Taupo. Crews leaving site.
• Can keep one lane closed
• Site will run as it has previous two nights with utilities and monitoring support.
• Resources back on site 7am
• Tartners and GP Friel to be onsite tomorrow, Rambo’s on call
21-108
Page 36 of 44
• Walter will drop off food to monitoring staff.
• Rahui started at 1pm – 2 weeks
Sunday 25/7 12pm
Paremata UPDATE 17
Unfortunately there has been a delay in the arrival of the specialised fittings from Auckland, which
will now arrive after 21:00 (9pm) tonight. Consequently we are putting today’s work on
hold. Sucker trucks have been mobilised to assist with minimising overflows at peak times and work
will resume tomorrow morning.
Thank you for your patience and we apologise for the inconvenience.
Sunday 25/7 5pm
Paremata UPDATE 18
• Need to notify GW Good progress
• Put in patches – blown up – gone in well and not cracked the pipe
• Pipes out of shape – 3m stub north 2m stub south, ready put in the final link ready to charge
(probably around 1hr before we can turn on the pumps)
• Look in the pipe – can see bend northern end, pipe significantly deteriorated. South side
roof disappearing – goes quite a way
• When connect do slow charge up, get bedding in then expose gibaults to check integrity.
• Change over of staff at 8pm. Reduced staff.
• Run 1 pump 6B and back in auto tomorrow morning.
• Tidy up works to do tomorrow.
• Gong to get cross harbour pipeline repaired tomorrow
• Need to ensure there is no overflow from 6A – manhole at the school is the lowest point.
• 6A 1 pump operational with diesel pumps as back up for wet weather.
• Check out if level control can be put on diesel pumps (Rambo’s).
• Starting to backfill by 6pm.
• 4 sucker trucks on standby for the night
• Effect on GP Friel planned work from this failure (Ian)
Sunday 25/7 8pm
Paremata UPDATE 19
• Traffic management working alright.
• Pipe up and running, patches provided the structural integrity, not leaking
• Backfilling
• Sucker trucks gone
• Traffic management still onsite - Station Rd, SH1
• Aim to remove TM mid
21-108
Page 37 of 44
• Monitor station Rd and drive by of site
• Alarm’s 6A (Station) have been reduced – will alarm earlier to avoid problems at the school,
a bit of rain expected
• 2 Sucker trucks on site
• Fence off diesel pumps
• SAP disinfect area around station rd (6:30pm)
• Keep GWRC informed about carparking.
• Traffic management on site to assist at school drop off and pick up.
• Have 6m left
Next steps;
• Temp solution – procure ready for next break
• Longer term solution
21-108
Page 38 of 44
Aotea pipe break/Paramata overflow Enteroccoci monitoring (cfu/100mL)
18/07/2021 19/07/2021 20/07/2021 21/07/2021 22/07/2021 23/07/2021 24/07/2021 25/07/2021
Final
Final
Final
Final
Final
Final
Final
Final
Wi Neera Drive boat ramp
3100
770
180
2100
4500
220
65
76
Pauatahanui Inlet Paremata Bridge
1300
980
320
130
44
560
48
16
Pauatahanui Inlet Water Ski Club
1200
1100
530
60
96
690
20
8
Plimmerton South Beach
1500
1100
400
120
1100
450
36
56
Karehana Bay Cluny Road (control site)
610
940
160
20
110
190
12
4
Plimmerton Beach @ Bath St
450
92
58
Takapuwahia Stream Outlet @ Te Hiko St
140
190
230
Porirua Harbour at Rowing Club
630
24
12
Weather
Overcast
Overcast
Rain
Clear
Clear
Clear
21-108
Page 39 of 44
Aotea pipe break/Paramata overflow Enteroccoci monitoring (cfu/100mL)
26/07/2021 27/07/2021 28/07/2021 29/07/2021 30/07/2021 31/07/2021
1/08/2021
2/08/2021 3/08/2021 4/08/2021 5/08/2021 6/08/2021
Final
Final
Final
Final
Final
Final
Final
Final
Final
Final
Final
Final
410
640
120
48
84
4
8
20
12
20
560
69
68
150
73
12
8
8
4
8
40
4
48
4
48
190
38
8
4
19
8
4
56
65
4
200
46
76
16
350
8
84
180
20
50
600
12
160
20
100
4
4
4
4
4
4
12
4
4
100
23
410
12
28
24
16
16
92
150
12
8
8
430
3400
110
38
40
220
12
12
3000
54
510
210
54
190
24
20
4
20
4
4
110
4
8
100
Rain
Rain
Clear
Clear
Clear
Clear
Partly cloudy
Clear
Rain
Overcast
Overcast
Overcast
21-108
Page 40 of 44
Hi James,
I’ve left a message on your phone related to this, but we have made several decisions pursuant to
s.330 emergency works since last Saturday morning. We are pulling together the documentation for
the event and decision-making sequences – as I’m sure you can appreciate this has been a complex
and evolving situation, which is still ongoing.
Can you please confirm that the notifications and updates so far have been recorded as notification
of the use of emergency powers?
Nga mihi,
Paul
Paul Gardiner (he/him
) Manager (RMA, Consents and Environment)
Tel 04 912 4400
DDI 04 912 4506
Mob 021 445 024
Private Bag 39804, Wellington Mail Centre 5045
Level 4, IBM House, 25 Victoria Street, Petone, Lower Hutt
www.wellingtonwater.co.nz
21-108
Page 41 of 44
21-108
Page 42 of 44
Team Leader Monitoring and Enforcement
Kaiārahi Rōpū Aroturuki me te Whakaūnga
Tel: 04 237 1404 I Mob: 021 948 720
poriruacity.govt.nz
From: Moana Wyatt <[email address]>
Sent: Thursday, 29 July 2021 10:16 AM
To: Hannah Toomaga <[email address]>; Derek Vos <[email address]>; David
Down <[email address]>
Subject: OIA 21-108 - Official Information request - Lawfulness of WasteWater Pipes and Discharges
Morning Derek/David
Please see the OIA below.
I expect the first question is a part transfer to WWL? Please let me know if you agree and I wil transfer it.
Hannah
I wil assign to you for Derek’s team to respond to the second lot of questions. Please let me know if you want my
assistance.
Thanks
Ngā mihi,
Moana Wyatt
Principal Advisor (Information)
Kaitohutohu Matua (Pārongo)
Tel: 04 237 1411 I Mob: 027 469 8532
poriruacity.govt.nz
From: [email address] <[email address]>
Sent: Wednesday, 28 July 2021 8:54 AM
To: Records Management <[email address]>
Subject: FW: [EXTERNAL] Official Information request - Lawfulness of WasteWater Pipes and Discharges
Hi Team
An Official Information Act request for you.
Kind regards
Sandy Betham
From: [FYI request #16216 email]
Sent: Tuesday, July 27, 2021 5:57 PM
To: [email address]
Subject: [EXTERNAL] Official Information request - Lawfulness of WasteWater Pipes and
Discharges
Dear Porirua City Council,
2
21-108
Page 43 of 44
In respect of recent failure of the wastewater (WW) main south of Paremata and the diversion of
wastewater flow to a redundant WW main on the western side of Porirua Harbour at Whitireia and
Onepoto, please provide me with the following information.
- details of the work undertaken by WWL and/or PCC;
- a copy of the current consents under the RMA (if any) that PCC/WWL has relied upon for: the
infrastructure; the work undertaken on it; and, the discharges from it, in respect of:
- the use of land in terms of section 9 of the RMA
- the use of land in terms of section 13 of the RMA
- restrictions imposed under section 12 of the RMA
- restrictions imposed under section 15 of the RMA .
- a copy of al correspondence within, and between, PCC/WWL about the lawfulness or otherwise
of: the specifically in terms of:
- the WW main as a structure;
- the recent work undertaken on it; and,
- the recent discharges from it.
Yours faithful y,
Brian Warburton
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