Monitoring Well Installation & Surveying

After the completion of the rip rap installation, the monitoring wells need to be installed to monitor the phreatic line at different distances along the embankment. Each well requires a 2"diameter PVC pipe, tape, cement and filter fabric.

On January 27th we went to the site to install one monitoring well and do some survey work to determine the cross section of the north embankment.

Using an auger Matt & Chai worked together to dig a hole approximately 25 meters south of the embankment and 4 meters deep. It takes a lot of effort to dig the hole so alternating diggers was key. As they worked, it became apparent that there was something stuck in the pipe; it turned out to be a frog! But they saved it.

The PVC pipe was wrapped with filter fabric and inserted in the hole then the space around the pipe was filled with sand. The top of the pipe is protruding from the ground. Concrete was poured around the well to keep it in place. A successful installation.

In the meantime Linda, Maria & Ceda surveyed from the watergate to the north embankment about 10 points using the measuring rod and level.

While we were there we studied the cracks just north of the dam. The largest seems to be 30 feet long from the edge of the dam and, using a make-shift plumb, it measured as much as 1'8" deep as seen below.

After about 4 hours the well was complete, and we reached the north embankment with our surveying. It was time to head back in time for Chai's class, just before sunset.

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