Raking liability aside when you rake the leaves

I’m enjoying the fall colours Down East like everyone else. The forest and the falling leaves, and those that end up on the path where I walk my dogs are something else. The dappled sunlight in the forest is a special sight especially after a light rain when the leaves are glistening in the sun. What’s not to like?

But it hit me recently when I had Rosie and Lily out for their morning pee run that these wet leaves on my sloping lawn are slippery – wet from rain not dog pee. I was a bit surprised.

Later when I was walking down the timber stairs from my deck the same thought occurred. There weren’t many leaves on the stair but when I slid my boot across the few, I could see that a lot of leaves might reduce the skid resistance of the timber enough to cause a slip and fall. No question a lot of wet leaves on a sloping, wet lawn would reduce the resistance. I’m careful now when I walk down a wet slope in a field overlooking Settle Lake in Halifax where my dogs run around like crazy.

How is this relevant to the purpose of this blog site “…to explain the nature and methods of forensic engineering and expert services”?

Well, who would have known wet leaves could cause someone grief? And is there a responsibility to rake the leaves everywhere in public places to reduce the liability?

It’s relevant because some might wonder, can you test the skid resistance of a leaf covered timber stair or a wet, leaf covered lawn? You certainly can.

I tested the skid resistance of the wet floor in a dry sauna where a woman had slipped and fallen using the skin from a pig’s belly. The skin is very similar to that on a person’s foot. I couldn’t use the woman’s foot and cause her to slip and fall again. Although I did think briefly about how I might have used her foot.

If you can measure it you can deal with it. (Refs 1 to 4) I believe you can measure everything including the frictional resistance of wet, leaf covered surfaces, and even the forest floor. Sometimes the measurements are rough but rough is better than nothing.

So, sweep those stairs, rake that lawn, and take care where you walk in public places.


  1. Osmond, Jack, “If you can measure it, you can manage it”, As quoted several years ago
  2. If you can measure it you can manage it, even if it’s a real mess like a car or truck accident. Posted June 23, 2016
  3. “Taking the measure” – forming an opinion of the cause of a fatal motor vehicle accident. Posted February 15, 2016
  4. “If you can measure it you can manage it” and do thorough forensic engineering and cost effective litigation. Posted June 18, 2015

(Posted by Eric E. Jorden, M.Sc., P.Eng. Consulting Professional Engineer, Forensic Engineer, Geotechnology Ltd., Halifax, Nova Scotia, Canada October 25, 2021 ejorden@eastlink.ca)   

What is civil engineering?

I’m a civil engineer by degree, but what exactly am I? What do civil engineers do? This question came to mind as I was recently drafting the blog, “What is forensic engineering?”. I thought, what would I say if asked? I was spooked because its many things. Where do I start?

Why not some fascinating history?

It’s the oldest engineering profession dating back to the first time someone placed a roof over his or her head or laid a tree trunk across a stream to make it easier to get across, and made certain these structures were strong enough. Then cut a road through the forest between the stream and the roofed-over abode. (Ref. 1)

It’s old if you just date it from the time of the Great Pyramid at Giza – about 4,600 years ago – the only one of the seven ancient wonders of the world that still survives. There are no records but the mathematical patterns of the structure and the internal passages suggest advanced planning and engineering – good civil engineering.

I studied construction of the Pyramid one time. The Pyramid hasn’t failed but a basic task in forensic engineering is learning how a structure was designed and built in determining the cause of a failure. Forensic archaeology is a field of study. (Ref. 2)

The Pyramid is a classic example of structural, foundation and geotechnical engineering – civil engineering disciplines – that had to accommodate differential settlement across the base of the Pyramid.

There’s a great weight on the foundation soils in the centre of the Pyramid, and lots of foundation settlement there. There’s little weight and settlement at the edges of the Pyramid. The result is differential settlement of the Pyramid’s foundation.

Hmmmm, why no cracks in the sloping sides of the Pyramid – a normal result of differential settlement? The reason is a simple, civil engineering solution – and a blog topic for another day.

Come forward to the 18th century and civil engineering is still quite old. Like said, it’s been around since the beginning of human civilization, since the appearance of Sapiens (Ref. 3) but it was not until more recently that the term civil engineering was coined to refer to the design and construction of civilian infrastructure. This as distinct from military infrastructure.

John Smeaton was the first person to call himself a civil engineer. His design of the Eddystone Lighthouse near Cornwall, England, 1756 to 1759, was based on his construction experience and thorough research – civil engineering.

The Institution of Civil Engineers was founded in London, England in 1818, and the profession was formally recognized in 1828. In time, comparable professional associations were founded in Canada, the United States, Australia and elsewhere in the world.

I also understand that a distinction was made between an engineer and an architect about this time or not too long afterwards. They were seen to be one and the same till then.


Civil engineering is not unlike an umbrella profession for a number of specialties that have developed over the years – 17 by my last count. (see Appendix) It wasn’t long till specialties were recognized in the planning, design and construction of the structures that comprise the infrastructure – the built environment – of our villages, towns and cities.

Specialties in the beginning like structural, foundation and geotechnical engineering. Soon highway engineering to get us from one village to another, then water supply engineering, and, of course, sanitary – now environment engineering – to get rid of waste and dirty water.

And because components of structures break and don’t work right, and structures collapse and fall down, and accidents happen and people get hurt, forensic engineering came to be.

At some point, mechanical and electrical engineering appeared outside the civil umbrella dealing with things that move, and design and construction involving more than basic electricity

A list of civil engineering specialties might look like the following to those of us who live in or near a town or village:

  1. Structural design engineering
  2. Foundation design
  3. Geotechnical
  4. Construction engineering
  5. Highway
  6. Environmental (formerly, sanitary)
  7. Water supply
  8. Forensic engineering

For example, Structural engineers design the steel, concrete and timber to support the structure. Foundation engineers design the footings and piles to support the structure. Geotechnical engineers find a layer of soil at the construction site that is strong enough to support the foundations that support the structure. Construction engineers build it. If anything goes wrong, Forensic engineers fine out why.

You take a degree in civil engineering and study a little of each of the above, then work and gravitate to one or the other and study more. I got my first degree in civil then moved onto geotechnical then to forensic.


What we see on a day to day basis is pretty common on the East Coast, as elsewhere – like, low and high rise buildings, houses, roads and sidewalks, power lines, propane tanks, wharves, water pipes, sewage pipes, storm drainage pipes and highway bridges – all involving a civil engineering specialty of one kind or another.

But get away from the mundane urban scene and civil engineers have designed and constructed some impressive structures since the Pyramid. In fact, more impressive than the Great Pyramid if I may be so bold.

These are reflected in the list in the Appendix as identified by the American Society of Civil Engineers (the list has an “only in the U.S. of A. tone” as noted in a postscript to the list)

I was quite taken during my research for this blog to learn that some suspension bridges are designed with a fin to control the effect of the wind – just like the fin on a whale to control the effect of water. One bridge failed out west one time because the wind made it wobble and shake too much.


What is civil engineering? You are surrounded by it from dawn to dusk and from birth to when you take your final leave.

You do the following on any given day in between, regardless your civil engineering specialty, and how mundane or impressive the structure:

  • Collect data on the structure and it’s purpose,
  • Analyse the data,
  • Design your part of it according to your specialty beneath the umbrella to perform as intended
  • Then ensure it’s constructed as designed.

Boring at times, as in same old same old, but where would the built environment be – the civilian infrastructure – without civil engineers?


  1. Google, Doctor. Thanks to Dr. Google for some comment and insight on the blog. October, 2021
  2. Catling, Christopher and Bahn, Paul, The Complete Practical Encyclopedia of Archaeology, (see page 226) Annes Publishing Ltd 2013, England
  3. Harari, Yuval Noah, Sapiens, A Brief History of Humankind, McClelland & Stewart, Canada, 2014


Civil engineering is an umbrella discipline for engineering specialties like the following:

  1. Planning
  2. Design engineering
  3. Construction engineering
  4. Structural engineering
  5. Foundation engineering
  6. Geotechnical engineering
  7. Forensic engineering
  8. Highway engineering
  9. Bridge engineering
  10. Water resource engineering
  11. Environmental engineering (formerly, Sanitary)
  12. Hydraulic engineering
  13. Municipal and urban planning
  14. Coastal engineering
  15. Tunnel engineering
  16. Earthquake engineering
  17. Survey engineering

The members of the American Society of Civil Engineers (ASCE) ranked the 10 greatest civil engineering achievements as:

  1. Airport design and development
  2. Dams
  3. Interstate highways
  4. Long span bridges (e.g. suspension bridges)
  5. Rail transportation
  6. Sanitary land fills/solid waste disposal
  7. Skyscrapers
  8. Waste water treatment
  9. Water supply and distribution
  10. Water transportation

Postscript: I think they messed up in not including tunnels like those through the Alps and the one beneath the English Channel from England to France – civil engineering extroedinaire.

(Posted by Eric E. Jorden, M.Sc., P.Eng. Consulting Professional Engineer, Forensic Engineer, Geotechnology Ltd., Halifax, Nova Scotia, Canada October 15, 2021 ejorden@eastlink.ca)