It's All in the Details

We have a project soon to start. There are plans, which show what they want, but lack some of the things required to lay the project out.

What's missing? Control points, with coordinates. I need a minimum of two, since my survey instrument (total station) only works with known points. Even if I had a GPS instrument, I'd still need coordinates to work from.

So, if they aren't available, I'll need to find all the property corners, create some baselines, establish points and use the plans to determine the layout points for offsets to center lines and boundaries. Any curves will be scaled. From that, I can determine a point of tangent, point of curve and the radius.

That's all a lot of work, considering a survey crew visited the site, has all the information and should have placed some temporary benchmarks for layout.

One of the biggest problems I face on too many projects is the lack of knowledge by those that order the survey. If you pay for such a thing, demand control points for reference. If enough are available, anyone can use a tape to find a point on the project.