New rail bridges at Ohau Point

According to NZTA's newsletter, 

Six new road and rail bridges are being built near the largest landslides that came down near Ohau Point north of Kaikoura. The bridges are being built to span areas where loose material from slips high in the mountains is being washed down to the coastline. As construction ramps up, five crews will be working on all six of the bridges. Next week piling cranes, piling hammers and a drill rig will begin arriving on site to install piles for the six bridges. They will be built at road and rail level with crews digging down to between 4m and 6m to create a space under each bridge for the material to flow out under. Each rail bridge will be 12m long and 4.6m wide, while each road bridge will span 18m and be 12m wide. 

Now from this I assume this means three rail bridges and three road bridges. The article doesn't say exactly where but it seems likely these three flows shown just south of 214 km. Basically out of sight to the left you have Bridge 116 and Tunnel 19. So I guess these may well be 116A, 116B and 116C but we will see what Kiwirail choose to call them.

MNL bridge 107 replacement

Photo: NZTA
Bridge 107 north of Kaikoura being replaced

Kaikoura Earthquake repair updates

I stopped posting the reports weekly as it was taking me a lot of time to pull all the bits out of them and illustrate, considering the information in them isn't always up to date and they tend to come out as much as a week after the stated date of publication.

The focus has all been on the highway with the well publicised closures of SH1 south of Kaikoura due to a big new slip between Puketa and Goose Bay. However there has been work on the Main North Line in particular at several overbridge sites at Parnassus, Waima and Oaro where a lot of repairs have been needed. Also the main line and loop are being relaid at Pines just south of Clarence where there is a big problem with an upthrust in the ground of four metres resulting in suddenly changed ground levels, this forced the track well off its normal alignment and has also affected the highway. The nearby Clarence River bridge which is quite a major structure needs significant work and the highway bridge was also affected. At Mangamaunu both the highway and the railway are being realigned around a major slip site, which I think means they are building new embankment and seawall probably. There are also five railway tunnels being repaired.

The aerial photos I have been making use of only cover a coastal strip (I had hoped they would include the inland highway route, unfortunately this is not the case) but Google Earth has updated its coverage for much of the area to cover the timeframe after the quakes, thus we can have a view of the whole route although their resolution is nowhere near as good. However the Linz photos do cover a stretch of SH1 between Hundalee and Oaro which is well separated from the railway line, this is really the only major route differentiation along nearly all of the Picton-Chch highway.

If you want to have a look at the Linz aerial photos yourself in a web browser this is pretty easy to do. Just go to the address below:

• https://data.linz.govt.nz/layer/3529-kaikoura-earthquake-02m-aerial-photos-2016/

On the left side should be the description of the data layer -title is 

Kaikoura Earthquake 0.2m Aerial Photos (2016)

You can see near the top left an orange + sign. Just click that (it should then change into a red - sign) and the layer is loaded onto the map shown at the right. Then just drag, zoom, scroll etc that map until the section Parnassus-Ward comes into view and you should be able to see the aerial photos.

Tirohanga Stream Bridge 129 / 252 km MNL

Photos of this bridge on the Kiwirail facebook page show the severe twisting it encountered in the quake. The embankment has also slumped noticeably at one end.

NZTA Earthquake Repair Update 31/3/17 [1]

The big news overall this week has been the closures of the highways because of weather related events. A closure of SH1 south of Kaikoura late last month was necessary in order to remedy new slips that had come down at a number of sites between Goose Bay and Puketa, as I have mentioned before. Just as the highway has reopened again the tail end of the Cyclone Debbie storm has caused more damage and forced it closed as there have been big mud slides at some locations. SH70 inland from Waiau to Kaikoura has also been hit by the weather and is open with restrictions at the present time.

Now for the key repair works and sites for this week.

This is the first big slip north of Kaikoura, just past 205 km on the MNL, and known to NZTA as "Site 1A". You can see here where a temporary road was put around the slip by crossing over the railway line. What's going to be happening here from this week is a new alignment of the road and railway line past this slip.

This is Half Moon Bay at MNL 211 km, just north of KRN Tunnel 18. This was originally one of the smaller slip areas with an estimated removal volume of 5000 cubic metres. However, due to the recent weather conditions, 10,000 cubic metres of material is currently being removed from the slip faces and this work will continue for the next few weeks.

Site 3 removal works last week (NZTA photo)

Work continues at the massive slip at Site 6 - Ohau Point. This photo is from a Beehive press release of about two weeks ago. (The railway is in tunnel at this location)

Site 7 is just north of Ohau Point at 214 km. Work is underway sluicing and scaling the slips to get the material shifted. The estimated total volume is 20,000 cubic metres.

Site 8 is just to the south of KRN Tunnel 20 and 217 km. The estimated volume to be removed here is 41,000 cubic metres making it one of the larger slips being worked on, and work has been happening here this week too.

Just north of MNL 259 km is the Waima Overbridge, known to KRN as Bridge 132. 

NZTA has had excavators at work at Waima digging out the culvert that carries the railway lane under SH1 at this location so that the structure can be repaired. 

I'll need to make another post to complete this update so that should be ready tomorrow.