Down I went again early this month, #2. This time a good reminder of the relationship between site conditions and the causes of slip, trip and fall accidents. I don’t recommend it but the accident opened my eyes yet again and added to my experience investigating these types of accidents. (Ref. 1) You can’t beat personal experience but I would have passed this one up in a heart beat.
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My day started as usual by taking my two golden retrievers, Lily and Rosie, for an hour’s walk in the green belt near where I live. The green belt is a large, mixed forest of hard and soft woods at the rear of residential properties and along lakes.
The area is so well covered with forest that it’s known as Forest Hills in the City of Lakes. A nice place to live and a great place to start your day “forest bathing”; shinrin-yoku in Japanese. My dogs love it too, running like crazy through the woods and into and out of the lakes and mud holes.
An asphalt covered path winds back and forth through the green belt, along the lakes and beneath a road overpass.
The path is covered with snow after a storm, and a mixture of snow and ice after an East Coast storm that goes from snow, freezing rain to rain, then back to frozen, wet snow.
The amount of snow and ice on the path also depends on the forest cover and also surface and groundwater runoff from the forest beyond the path. (You can see the surface of groundwater – the water table – in a dug well) The groundwater flows onto the forest floor where the water table intercepts the ground surface – same place we get nice spring water in the summer.
I knew I would have to pick my way over and around some icy patches on the path Thursday morning so I wore cleats on my boots. These are rubber soles with sharp, steel cleats embedded in the underside of the sole that straps on your boot. They are good on ice but you do need to be a bit careful on a smooth, hard icy surface that slopes a little.
It was a cold, bitter morning so I wrapped up warm. I also have collars and leases for Lily and Rosie – they manage without winter gear seeing as they’re running and playing hard in the forest. I fitted Lily with a lease to her collar and hung Rosie’s around my neck. Lily has a mind of her own and tends to dash here and there so I need to keep her close till we get beyond the overpass on Gregory Drive at the start of our walk and the road there.
Water flows across the path at the overpass almost year round and the ice gets quite thick at times in the winter.
Careful, I was, no question
I picked my way at the start of my walk across a mix of ice, frozen, water-soaked snow, and exposed asphalt, and under the overpass. The path is quite steep down to and approaching the overpass then levels off some.
I walked along the side of the path on the down slope side beyond the overpass. The path was quite icy and even with cleats I not want to chance it. The edge of the path had more traction on a rougher surface of ice and frozen, water-soaked snow; a safer place to walk.
But, not careful enough
Nevertheless, down I went, hard! I lay there for a few seconds, more surprised than anything, a tad shook up. Then I lifted my head a little, and was surprised at the amount of blood dripping on the snow – a lot. I learned later from ski friends that there are a lot of blood vessels near the surface of the head.
Short minutes later I stood, took stock and decided, while shook up and bloody, I was okay to continue my walk. I had a couple of hankerchiefs and got them well soaked with blood over the next hour as Lily and Rosie and me continued our walk. I tend to get up and keep moving when broadsided by life, at least that’s my attitude.
Through it all my dogs stayed by my side when I was down. A nice feeling. Then, when they saw me walking again, they took off into the forest running and playing and having a laugh and a giggle.
Why did I fall?
So, what happened? Why did I fall? My immediate thought, even while laying there dripping blood, was that I tripped and fell on a piece of icy, frozen snow at the edge of the ice covered path, a piece standing a little prouder than the rest. I seem to remember actually thinking like that and also feeling a sensation at the toe of my right boot. All of this within seconds.
There’s no question I tripped and fell on a rough surface. Also that I was moving along like you do when you got a fairly calm dog like Lily on a lease, albeit a little more carefully still. And that I was walking on a thickened sole with cleats. But all of that was normal for me in the winter time these many dog-years on. I walk through the forest every morning and often on cleats in the winter time.
Conditions cause problem
I’ve since thought that the chunk of ice/frozen, wet snow was the cause of my trip and fall accident and the conditions at the overpass the lead-in. In engineering this is a way of seeing a situation as a product of a set of conditions leading to the cause of a problem. Prevent the conditions developing – the icy conditions at the overpass – and the cause of a problem won’t rear its ugly head, the chunk of ice and snow at the edge of the path in this case.
The path at the overpass is covered by several centimeters of ice a lot of the time in the winter – the conditions – and wet in the summer. The water on the path is surface water from the forest floor on the up slope side of the overpass and from the ground beneath the forest floor – the water table.
You can see this water on the path almost year round. It’s there because of poor design, construction and maintenance of site drainage at the overpass. Salt is placed on the ice but it doesn’t help much.
The water is there waiting for freeze-up in the winter to cause accidents. Kids actually walk through the forest to get to the Joseph Giles Elementary School in winter rather than across the icy path. Simple solutions to this type of problem are in place elsewhere in the green belt in the City of Lakes but not at this site. (Ref. 2)
The personal, take-away experience from this?:
I was reminded that you can model a slip, trip and fall accident site during a forensic investigation as a set of condition and a number of causes depending on where you’re at on the site. The conditions vary depending on location and the causes of accidents vary too.
I had good cleats on my boots but knew they would be unreliable on smooth, sloping ice – reliance on them could be the cause of me slipping and falling. But that didn’t happen here – I didn’t slip. I forgot that the rough, frozen wet snow at the edge of the smooth ice could be the cause of me tripping and falling – as happened.
The tiniest conditions need to be investigated at the site of a slip, trip or fall accident.
References
- My personal slip, trip and fall accident, #1 Posted September 2, 2021
- Dewberry, Sidney O. and Matusik, John S., Land Development Handbook, Planning, Engineering and Surveying pp 1014, Chapter 14 Storm Drainage Design, pp 513 to 576 McGraw Hill
(Posted by Eric E. Jorden, M.Sc., P.Eng. Consulting Professional Engineer, Forensic Engineer, Geotechnology Ltd., Halifax, Nova Scotia, Canada. February 26, 2023 ejorden@eastlink.ca)
(Note: The foregoing blog is not a report on a forensic engineering investigation)