So, for those who have not heard the saga of our bridge, time for an update.
We have a small stream running through the front paddock, about a meter wide. Takapu Stream. The bridge that goes across it is not very large, and is a somewhat ramshackle affair having been built from this-and-that over the years. Hardwood sleepers, I-beams, railway iron, all capped by 55mm steel tubes acting as a cattle-stop.
Back last January 2010, Transpower was pouring new concrete footings for 66kV line, these are the smaller steel pylons that date back to the 20’s or 30’s, and were installed without concrete, just stuck into the ground. As our bridge is nowhere near “engineer certified”, they elected to bring in a big tracked concrete mixer which would meet the concrete trucks down at the road, ford the stream, and take it up to the site via the farm tracks (check out the photos from the Jan 2010 blog posts to see the big yellow moster)
Problem is, one of the concrete truck drivers didn’t follow instructions, and took his 22 ton truck across the bridge.
A week later, we noticed the Vitz bottoming out when driving across. Uh-oh. The southwest corner had dropped about 10 cm, and the big concrete bastion in that corner had cracked through and was pulling away. Time to call the contractors. They agreed it was their problem, and they had to fix it.
Enter plan A- jack up the bridge, pour a new footing in that corner. Their contractor came in, and upon examining the bridge and the plan, refused to do the work. In his words “either the bridge will fall apart when I jack it up, or I will finish the job, and it will fail in a year or two, and I will get the blame.” I had to agree with him. It was a dumb plan. Cheap, yes, but dumb.
In retrospect what they should have done is pulled out the old bridge with a digger, poured proper concrete bastions on each side, and dropped a pre-cast deck on top. Could have been done in 2 or 3 days of work. But no, they had to try and do it the legal way.
Takapu Stream is a named watercourse. So they needed a resource consent to go with the building consent. And engineers plans. And a hydrological assessment of the 50-year flood flows based on the cachement. Oh, and add an accurate GPS survey of all the land within 100 meters. Time consuming, expensive. We got a copy of the consent, very informative. But the whole process ate many months.
The plan was now to put in a 3×1 meter culvert, which would be highway grade, meaning it could take any highway load, 13 tons per axel. Sweet!
Last December I heard it was “all go.” They just needed to order the culverts, which were not “off the shelf” and needed custom manufacture. The problem was, it was mid December, and the factor shut down for summer holidays. So the soonest they could get to work would be late January. No problem I said.
SO I call up in February. “What’s up with the bridge?”, I ask. Problem, they have a new general manager. He wants to know what this expensive bridge is all about. He wants to fight out who will pay (contractor, Transpower, Allied Concrete). Time goes by. Finally I send a letter to the GM telling him to get on with it respectful, but forceful).
Finally, at the end f May, we are “all go” again. But wait, there is a new delay! The culvert has to cure for at least 2 months before installation! So the earliest we can get work done is end July/early August. And because the work is in a stream, and winter is peak water flows, they might have to wait until Spring.
And then a few weeks ago we got a major rainfall. The stream went over the bridge again (at least the 4th time in 7 years, it doesn’t help that the bridge is now a good bit lower due to the ongoing degradation).
Last Monday I noticed that the woodwork under the bridge (on the western, more damaged side) had fallen away into the stream leaving the bank exposed, and it had scoured back nearly 30 cm. Problem is, the concrete beam holding up that end of the bridge in probably only 40 or 50 cm wide. We are approaching “precariously perched”, and still have at least 6 weeks until the culvert is ready.
Hope we don’t get any more heavy rainfall, you know, in like, winter, when it rains a lot.
Watch this space.