The tranquil sea coast in the heading is deceptive.
Many forensic engineering problems are caused by water or water is a factor in their cause. J. Knoll photographed Prospect Bay, Halifax, Nova Scotia, Canada on a nice day.
Other days are not so nice along the 1,000s of kilometres of Atlantic sea coast – almost as long as Canada is wide. Nor are the 1,000s of rivers and streams that flood – and they certainly have flooded this past June with the near record rainfall – 213 ml (8.4 in) at the Halifax airport compared to a normal 98.3 ml (3.9 in).
The rivers and lakes are still flooding as the land sheds the rainfall in runoff to our watercourses. And the lakes are overtopping their banks – there are more than 4,000 lakes in Nova Scotia. That’s just the water you can see on the ground surface.
There is also the groundwater, the water table, that you can’t see. Water that is just below the ground surface or down deep, and fluctuating up and down all the time – certain to be well up and high after our rains in June.
Ground water flows through the ground much like a river flows on the land; welling up behind obstacles buried in the ground – e.g., foundations and basement walls, like river water wells up behind a boulder in a stream.
It’s been said that if you could take the water out of the ground, out of the soils and rocks beneath our feet, you would reduce foundation and ground engineering problems to a fraction.
The camera operator in the heading is filming the re-enactment of a fatal MVA from a sea king helicopter during a forensic engineering investigation. I set up a full scale test site at Shearwater airbase complete with: 1. A traffic lane, 2. An obstacle in the lane, 3. A vehicle, 4. Monitoring devices to track vehicle behaviour on striking the obstacle, and, 5. Film crews to record the tests.
The sea and snow – frozen water, were factors in the fatal accident.
The surveyor in the heading is checking the adequacy of the underpinning of a structure during a forensic investigation.