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Technology can be great. For a few years now we have used Trimble software and hardware to produce GPS topographic surveys for drainage design. Gone are the days of laser levels and judging the ground by eye, which to be fair, served my father and grandfather well. 1/8
Technology can be great. For a few years now we have used Trimble software and hardware to produce GPS topographic surveys for drainage design. Gone are the days of laser levels and judging the ground by eye, which to be fair, served my father and grandfather well. 1/8
Now we tow a mini tractor to the field and drive it along the tramlines and any low spots whilst its records a level position every 3m. This produces alot of data, 1000s of survey points, something never possible before. But data for data sake is pointless, does it help....
Well yes, often quite a small difference but still a difference. For example, this is a field I designed before we brought the technology, as you can see the main (the green line) skips pass a possible outlet (the pond) and down to the brook.
The reason for this? At the time I was unsure if the lateral drains (the red lines) at the top of the picture would fall all the way to the brook. The field flattens out with a slight valley where the main is, I was not sure if we could grade through the valley.
In additions, I was also unsure about the area just to the south of the pond where once again the land flattens.
I had the choice of surveying the whole area or playing it safe and putting a new main in. Surveying the whole area in sufficient detail would have been very time consuming and with two potential issues I opted for the extra main.
If you don’t know for certain or if your only 90% certain then after a few mistakes caused by inexperienced and over confidence most designers ending up opted for the safe option, I did/do.
However the GPS survey proved that both worries were unfounded. The Laterals will flow towards the brook just fine. So the new design has the main outleting into the pond and the laterals carry on towards the bottom of the field
This means the length of the main is reduced, replaced with cheaper and smaller sized lateral drains. The cost saving is relatively small on this job, my back of a fag packet calculation says only 2.7%, but still 2.7% cheaper is better than no saving.
Our prices have held steady for a while now, the reason why is small improvements in efficiency this time via technology.
