Take shots on the water level on each side at the same time with different equipment, then set a TBM on each side before checking the OFFICIAL BM with one set of equipment and traversing to the project site with the other.?ÿ Wham bam done.?ÿ Except for the quick communication from side to side to confirm getting the same elevation reading for water level.
How's that??ÿ Off by how much, you say??ÿ Obviously, one set of equipment is faulty.
Simultaneous GNSS on each side, fairly long session, post-processed together to use only common sats.. Repeat another day, different time of day. Apply geoid.
Take shots on the water level on each side at the same time
I don't think that will be as good as simultaneous GNSS.
If using water levels, you need stilling wells (buckets with small hole), a calm day, and readings at multiple (simultaneous) times. A lake that size might be okay. A bay will be trickier because of the flow of tides-you might be limited in usable times.
This is a harbor, so there would be differential results over time. But, if readings are taken simultaneously at points of similar distance to the mouth of the harbor (and using stilling wells) the results should be practically identical.?ÿ Running multiple tests would be fun.
If I could set something intervisible on each side of the bay, I would probably just shoot both directions with a total station. Take a GPS measurement on each side as a check, and move on.?ÿ
What are the tolerances? Who will prove you "wrong"? What happens if you are off by x amount?
If this is to just check a box, then my method works. If it is to extend geodetic control, then there would need to be another method.
Heights to be done in terms of the Christchurch City Council Datum
Nearest benchmark is on the other side of the harbour - 17km by road drive or 3.6km direct
The foremost authority I know in that part of the world is: W E Featherstone Western Australian Centre for Geodesy, Curtin University of Technology, Perth, Australia, W.Featherstone@curtin.edu.au
Where is your project on this view of the area??ÿ When looking at this in GoogleEarth I noted that their are quite a few more named bays other than the ones listed here.
I'd want to set a 5 gallon bucket on both sides, with a few holes in it. And, drive a peg, or rebar down to water level. This as a double check. And, to add perspective.
Where is your project on this view of the area??ÿ When looking at this in GoogleEarth I noted that their are quite a few more named bays other than the ones listed here.
Since you are playing in Google Earth...
Try to find 41 Tikao Bay Road in street view.
Note the search function puts it too far up the hill
