In this picture you will see that we have added water to each section of the large plastic container next to the sand.



This has not made any difference to the water levels in any of the small containers.

It does make it impossible to measure to the bottom of each of the submerged containers.

The different water levels that can be seen to confuse the measurements.

In cathodic protection monitoring each of these levels can be measured but the confusion of data can only be analysed using computers.