Printed from https://fyi.org.nz/request/3627-seismic-structural-performance-reports on November 05, 2025 02:04

Seismic/Structural Performance Reports

Fraser made this Official Information request to Upper Hutt City Council

The request was successful.

From: Fraser

Dear Upper Hutt City Council,

I request the following information as an interested ratepayer and resident:

1. The written portion (ie no need to include calculations) of any reports regards the current seismic performance of the appropriate primary water reservoir tasked with providing water to the Trentham area that Council holds.

2. A copy of the written portion (ie no need to include calculations) of any reports regards the current seismic performance, or expected current structural performance during flood events of the Silverstream Road Bridge that Council holds.

3. A copy of the written portion (ie no need to include calculations) of the last structural assessment and any individual asset management assessment/plan (last version) of the Birchville Bridge prior to its failure that Council holds.

4. A copy of the written portion (ie no need to include calculations) of any reports regards the current seismic performance of the Birchville Dam that Council holds.

Yours faithfully,

Fraser

Link to this

From: Jacqui McKelvey
Upper Hutt City Council

Attachment Letter to Fraser 2016.02.11.pdf
124K Download View as HTML

Dear Fraser

Please find attached a letter of acknowledgement for your request for information.

Regards,

Jacqui McKelvey
Administration Officer
Corporate Services

Upper Hutt City Council | 838-842 Fergusson Drive, Private Bag 907, Upper Hutt 5140, New Zealand
T: +64 4 527 2169 | E: [email address] | W: www.upperhuttcity.com | F: www.fb.com/upperhuttcitycouncil

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From: Karen Patterson
Upper Hutt City Council

Attachment Letter to Fraser transfer to GWRC 18.02.16.pdf
350K Download View as HTML

Hi Fraser

 

Please see the attached letter.

 

Can you please confirm receipt.

 

If you have any queries, please give me a call.

 

 

Regards

 

Karen

 

 

 

Karen Patterson

Registered Legal Executive

 

Please note my hours of work are 8.30am to 3pm

Monday, Wednesday, Thursday and Friday

 

Upper Hutt City Council | 838-842 Fergusson Drive, Private Bag 907, Upper
Hutt 5140, New Zealand

D: +64 4 529 0080 | T: +64 4 527 2169 | F: +64 4 528 2652 | E:
[1][email address]  W: upperhuttcity.com

 

 

 

Please consider the environment before printing.

 

--

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From: Mark Sutherland

Dear Fraser,

Acknowledgement of Request for Information

 

Thank you for your email dated 18^th February 2016, requesting information
regarding any reports on the current seismic performance of the Birchville
Dam that Council holds.

 

Your request is being followed-up and a reply will be sent to you shortly.

 

Yours sincerely,

 

 

Mark Sutherland

 

 

for
Luke Troy

General Manager

Strategy

 

ATTENTION: This correspondence is confidential and intended for the named
recipient(s) only. If you are not the named recipient and receive this
correspondence in error, you must not copy, distribute or take any action
in reliance on it and you should delete it from your system and notify the
sender immediately. Unless otherwise stated, any views or opinions
expressed are solely those of the author, and do not represent those of
the organisation.

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From: Fraser

Dear Karen,

I thought this may be the case but wasn't sure. Thankyou for your response and forwarding on my request.

Yours sincerely,

Fraser

Link to this

From: Sharon Hornal

Attachment 120373 Dam inspection May 2013 1218302.PDF.pdf
316K Download View as HTML

Attachment 120373 Dam investigation 1989 1506052.PDF.pdf
1.5M Download View as HTML

Attachment Birchville Dam safety surveillance 721182.pdf
24K Download View as HTML

Attachment Damwatch safety review Mar 2013 1248388.pdf
6.8M Download View as HTML

Attachment OIA Letter response OIAP 7 1044.docx
509K Download View as HTML

Good afternoon Fraser

 

Please find attached the response and supporting documents in response to
your OIA request 2016-014.

 

This link should be included in the email response to Fraser too please:
[1]http://www.gw.govt.nz/assets/council-pub...

 

 

Regards

Sharon

 

Sharon Hornal | Executive Assistant to General Managers: Environment
Management & People and Customer Groups, and Te Pou Whakarae

GREATER WELLINGTON REGIONAL COUNCIL Te Pane Matua Taiao

| Shed 39, Harbour Quays | 2 Fryatt Quay | Pipitea

PO Box 11646, Manners St, Wellington 6011

Tel: 04 830-4234 |

[2]www.gw.govt.nz | [3]www.facebook.com/greaterwellington |

 

 

 

 

ATTENTION: This correspondence is confidential and intended for the named
recipient(s) only. If you are not the named recipient and receive this
correspondence in error, you must not copy, distribute or take any action
in reliance on it and you should delete it from your system and notify the
sender immediately. Unless otherwise stated, any views or opinions
expressed are solely those of the author, and do not represent those of
the organisation.

References

Visible links
1. http://www.gw.govt.nz/assets/council-pub...
2. http://www.gw.govt.nz/
3. http://www.facebook.com/greaterwellington

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From: Fraser

Dear Sharon Hornal,

Thank-you to Greater Wellington for their prompt and thorough reply.

Yours sincerely,

Fraser

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From: Sharon Hornal

I am out of the office today 26 February.

 

If you email is urgent, please contact either:

 

[email address] or [email address] otherwise I will
respond to your email on my return.

 

Regards
Sharon

 

 

 

 

 

ATTENTION: This correspondence is confidential and intended for the named
recipient(s) only. If you are not the named recipient and receive this
correspondence in error, you must not copy, distribute or take any action
in reliance on it and you should delete it from your system and notify the
sender immediately. Unless otherwise stated, any views or opinions
expressed are solely those of the author, and do not represent those of
the organisation.

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From: Sharon Hornal

Thank you Fraser, I have forwarded you email onto the writer of the response letter.

Regards

Sharon Hornal | Executive Assistant to General Managers: Environment Management & People and Customer Groups, and Te Pou Whakarae
GREATER WELLINGTON REGIONAL COUNCIL Te Pane Matua Taiao
| Shed 39, Harbour Quays | 2 Fryatt Quay | Pipitea
PO Box 11646, Manners St, Wellington 6011
Tel: 04 830-4234 |
www.gw.govt.nz | www.facebook.com/greaterwellington |

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From: Karen Patterson
Upper Hutt City Council

Attachment Letter to Fraser 09.03.16.pdf
432K Download View as HTML

Attachment Q 1 UHCC Water Reservoirs Seismic Assessment Report.pdf
6.5M Download View as HTML

Attachment Q 2 UHCC Silverstream Bridge Seismic Strengthening Report.pdf
6.3M Download View as HTML

Attachment Q 3 Brichville Bridge Inspection Forms.pdf
3.1M Download View as HTML

Hi Fraser

 

Please see attached letter and reports in response to your request for
information.

 

Can you please confirm receipt.

 

If you have any queries, please give me a call.

 

 

Regards

 

Karen

 

 

 

 

 

Karen Patterson

Registered Legal Executive

 

Please note my hours of work are 8.30am to 3pm

Monday, Wednesday, Thursday and Friday

 

Upper Hutt City Council | 838-842 Fergusson Drive, Private Bag 907, Upper
Hutt 5140, New Zealand

D: +64 4 529 0080 | T: +64 4 527 2169 | F: +64 4 528 2652 | E:
[1][email address]  W: upperhuttcity.com

 

 

 

Please consider the environment before printing.

 

--

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From: Fraser

Dear Karen,

Thank-you very much for the information provided as requested.

I have had a quick read of the information and it has raised a couple of queries - responses to which would help my understanding of the overall situation. I note it’s not really an official information request so much as a general inquiry, so hopefully there is someone who is happy to respond, and I highlight my appreciation for their time. I apologise in advance if they are a little basic, ill-worded or unusual!

I’m not quite sure of the protocol regards this as to whether it can be dealt with direct by council staff or whether I need to raise them through a local councillor – I’m happy to if required. A lot of the information is probably available publicly in various documents but hopefully I can address them directly and a few hours reading will be saved.

In terms of the reservoirs:
1.Has a decision been made on whether to strengthen Trentham 1 reservoir?
2.If so will it be strengthened to SLS (grade C) level only or will a higher performance level be targeted?
3.What is the timeframe for this work to occur and has a budget been set aside/planned? (Ie. I’m not after the amount I’m just wondering if there is a plan in place regards financing the work.)
4.Has the construction of a new Trentham 1 reservoir (which would meet ULS requirement) been considered? If so what was the cost estimate for this compared to the est. $430000 for remediation?
5.Has a timeframe for the strengthening of the other five grade D reservoirs been determined, if so what are the timeframes and has a budget been set aside/planned? (Ie as above)
6.Is there an intention to strengthen the grade C reservoirs to a higher performance? If so what is the timeframe for this work? What is the timeframe for Trentham 2 in particular?
7.Has the lowering of the Trentham 1 reservoir water level to 3.5m been undertaken to mitigate some risk in the interim? If not has it been considered/is it possible?
8.Have all the reservoirs Upper Hutt City Council owns/has responsibility for (presumably 16) been fitted with seismic shut off valves?
9.Are the reservoir connections configured so that one can be isolated from the network, or would physical works be required to route around a reservoir to allow the remainder of the network or proportion of a network to function in the event of a failure? Eg. To compare it to electricity are they connected in series or connected in parallel.

In terms of Silverstream Bridge:
10.I note from the report in 2006-7 that it was expected due to capacity that the bridge would likely need to be modified or replaced within 20 years. Is there any update regards this? Given that this would result in replacement within approx. 10 years time has this work been included in the Long Term Plan and is there a plan in place regards financing the work?
11.If it is no longer planned to replace the bridge in this time frame for any reason, is there an intention/schedule to undertake an updated assessment of the seismic performance to compare it against the updated bridge manual/standard? Ie Presumably the bridge standard at the time had basis in NZS:4203 whereas now utilises NZS:1170.

In terms of the Andrews/Birchville Bridge:
12.Can it be confirmed as per the recommendation in the inspection report that the flood debris was cleared from the central pier as recommended and that the scour resulting was confirmed as not exposing the piles of the original bridge pier - prior to the failure in October?

Thanks in advance.

Yours sincerely,

Fraser

Link to this

From: Karen Patterson
Upper Hutt City Council

Hello Fraser

I have forwarded your questions and comments onto the Asset Management and Operations team.

Do you have any other contact details where we can reach you?

Regards
Karen

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From: Fraser

Hi Karen,

Back after a bit of a break!

Ideally it would be nice to keep things in the same place, so a response via the site would be ideal.

I imagine this feedback would also help provide further background and clarity for anyone who stumbled across the information via a google search or similar.

Thanks,

Fraser

Link to this

From: Karen Patterson
Upper Hutt City Council

Attachment image001.jpg
21K Download

Attachment Letter to Fraser with attachments 2016.04.21.pdf
1.1M Download View as HTML

Hello Fraser

 

Please see attached letter in partial response to your further queries.  I
will be back in touch.

 

If you have any questions, please give me a call.

 

 

Regards

Karen

 

Karen Patterson

Registered Legal Executive

 

Please note my usual hours of work are 8.30am to 3pm

Monday, Wednesday, Thursday and Friday

 

Upper Hutt City Council | 838 – 842 Fergusson Drive, Private Bag 907,
Upper Hutt 5140, New Zealand
D: +64 4 529 0080 |  T: +64 4 527 2169 | E: [email address] |
W: [1]www.upperhuttcity.com | F: [2]www.fb.com/upperhuttcitycouncil

[3]UHCC_AP-2016-2017_Signature-banner-1

Please consider the environment before printing.

 

References

Visible links
1. http://www.upperhuttcity.com/
2. http://www.fb.com/upperhuttcitycouncil
3. http://www.consultation.upperhuttcity.com/

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From: Karen Patterson
Upper Hutt City Council

Attachment image001.jpg
21K Download

Attachment Letter to Fraser 27.04.16.pdf
894K Download View as HTML

Hi Fraser

 

Please see attached response to your further queries.

 

Please confirm receipt and let me know if you have any other questions.

 

 

Regards

Karen

 

Karen Patterson

Registered Legal Executive

 

Please note my usual hours of work are 8.30am to 3pm

Monday, Wednesday, Thursday and Friday

 

Upper Hutt City Council | 838 – 842 Fergusson Drive, Private Bag 907,
Upper Hutt 5140, New Zealand
D: +64 4 529 0080 |  T: +64 4 527 2169 | E: [email address] |
W: [1]www.upperhuttcity.com | F: [2]www.fb.com/upperhuttcitycouncil

[3]UHCC_AP-2016-2017_Signature-banner-1

Please consider the environment before printing.

 

References

Visible links
1. http://www.upperhuttcity.com/
2. http://www.fb.com/upperhuttcitycouncil
3. http://www.consultation.upperhuttcity.com/

Link to this

From: Karen Patterson
Upper Hutt City Council

Hi Fraser

I have now reposted my partial response to your request regarding earthquake prone buildings to the correct email address - please can you check and confirm. I am unable to remove it from the email stream on your request regarding seismic structural reports.

I also emailed a response to your further questions regarding seismic structural reports yesterday - can you please confirm that you have received that on the correct email.

Regards
Karen

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Link to this

From: Karen Patterson
Upper Hutt City Council

Hi Fraser

I have now reposted my partial response to your request regarding earthquake prone buildings to the correct email address - please can you check and confirm. I am unable to remove it from the email stream on your request regarding seismic structural reports.

I also emailed a response to your further questions regarding seismic structural reports yesterday - can you please confirm that you have received that on the correct email.

Regards
Karen

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From: Fraser

Dear Karen,

Thank-you for your answers to further questions raised.

Yours sincerely,

Fraser

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Things to do with this request

Anyone:
Upper Hutt City Council only: