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Discussion: how to map dam spillway

in: Orienteering; General;

Dec 31, 2015 2:05 PM # 
take a look at this image. It shows a dam, a spillway, and a basin. The spillway is all concrete, with an inch (or less) of water flowing on it.

It's not open land (yellow). It's not a water body (blue). It could be bare rock (grey). And in any case, signage around say "stay off spillway" (off bounds symbol possibly...).

input and comments welcome.
Dec 31, 2015 2:08 PM # 
Ask Fletch. He's good at getting washed away by dams.

Seriously though, if it says stay off, you should probably stay off. Maybe passable blue under that (with OOB overprint)?
Dec 31, 2015 2:31 PM # 
Paved surface with out-of-bounds overlay?
Dec 31, 2015 2:44 PM # 
Bare rock with outofbounds?
Dec 31, 2015 2:46 PM # 
here is a possible mapping interpretation...
Dec 31, 2015 3:08 PM # 
It's the same kind of crossable stream as the part lower down (below the basin), just wider. If it's prohibited, add purple.

Don't overthink these things.
Jan 1, 2016 12:34 AM # 
paved surface or bare rock (whatever is consistent for similar surfaces around the dam), with passable? embankments or rock faces on each side, and OOB overprint,

Even if an event organiser could get special permission for courses to cross the spillway, consider whether you would want this used in the range of potential flow conditions when there appears to be an alternative on the downstream side of the basin.
Jan 1, 2016 2:44 PM # 
"darn" spillway
Jan 5, 2016 3:39 PM # 
The grey works well, it's clear when you are there what it is.
Should there not be a solid black boundary edge between the grey of the concrete and the orange for the open land? Then definitely add purple hatch if it's OOB.
Jan 5, 2016 11:26 PM # 
Purple hatching might not prevent this:
Jan 6, 2016 2:04 AM # 
I guess they didn't know what the purple stripe symbol meant. I mean they probably thought they were legally trespassing so it was okay.
Jan 6, 2016 2:22 AM # 
I'm pretty sure use of a billycart is not permissible under either IOF or OA competition rules in foot orienteering events. Not sure whether or not a billycart qualifies as a "pedal-powered cycle" as defined in the MTBO rules.
Jan 6, 2016 3:01 AM # 
Blair, why is your department washing out the Sydney test?
Jan 6, 2016 3:03 AM # 
We feel sorry for the West Indies and don't want them to go home as 3-0 losers. (I am not as yet aware of any of my colleagues who have a financial interest in a draw, although a few of us thought about it).

The record total rainfall for a Sydney Test is 476 millimetres (Australia v Pakistan, 1989-90), so we've still got a long way to go.
Jan 6, 2016 8:58 AM # 
On the opposite tack, any chance of WA hitting 50C? Been within 3.5 the last couple of days.
Jan 6, 2016 11:35 AM # 
Where, in your oven?
Jan 6, 2016 10:37 PM # 
Don't think so in the immediate future. Marble Bar would get to 47 in more summers than not; the more interesting numbers were further north (44.9 at Halls Creek was 0.1 off its all-time record).

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