Bushwalk Australia

Hi All,

Just wondering if anyone has an idea of the correlation between how many mm of rain the Blue Mts receives, and how much the Kelpie Point river depth gauge increases? I.e. if there's 20mm of rain in the area, how much would you expect the Cox's to increase.

Kelpie point is currently at 0.6m, with 20mm of rain forecast for Friday and 20mm on Saturday, or thereabouts, would this render it uncrossable on Sunday?

Also any insight on the same issue for the Nattai and the Wollondilly rivers is much appreciated!

Thanks in advance for any responses!

matt_h wrote:Hi All,

Just wondering if anyone has an idea of the correlation between how many mm of rain the Blue Mts receives, and how much the Kelpie Point river depth gauge increases? I.e. if there's 20mm of rain in the area, how much would you expect the Cox's to increase.

Kelpie point is currently at 0.6m, with 20mm of rain forecast for Friday and 20mm on Saturday, or thereabouts, would this render it uncrossable on Sunday?

Also any insight on the same issue for the Nattai and the Wollondilly rivers is much appreciated!

Thanks in advance for any responses!

My recollection was that anything over half a meter or so at Kelpie would make the Cox uncrossable at either/both of Yellow Pup or Mt Cookem crossings? Nattai isn't uncrossable very often (can be though!) and drains pretty quickly after a flood but i'd be dubious about the Wollondilly after a lot of rain. In any case, if planning on doing Katoomba to Mittagong (which I've inferred from the post, might be wrong), I think large parts of the route remain closed from fires (eg. Scotts Main being part of Kanangra Boyd NP)? Could be wrong about that too.

Thanks for that.

Looking at the topo maps, Scotts Main Mange is either entirely within Blue Mts NP, and then for about 5km north of the turnoff to Byrnes Gap, Scotts Main Range forms the border between Kanagara Boyd and Blue Mts. Doesn't seem to be part of KBNP though.

BMNP stretches all the way to Wombeyan Caves road. This map may help in understanding the boundaries: https://www.nationalparks.nsw.gov.au/vi ... s-area/map

Yerranderie State Conservation Area, which covers the bit between Yerranderie and the Wollondilly River (where Nattai NP starts) remains closed. As does Yerranderie Regional Park, which covers the old township.

"This park is closed due to fire and flood damage. Do not enter this park." (See: https://www.nationalparks.nsw.gov.au/vi ... cal-alerts).

So there is no way to do the Katoomba to Mittagong route at the moment, even though large parts are open at either end.

I do remember trying to swim the Coxs River one time near Kelpie Point. It was kinda deep and fast at the time. We pulled back.

Cheers
Roger

When we waded across the Cox's River at Yellow Pup Spur on the weekend, the Kelpie Point gauge was reading 0.64m.

Although we were ready for a swim, it was a safe, thigh-height crossing. Perhaps the 2021 floods laid down some gravel for us.

matt_h wrote:Just wondering if anyone has an idea of the correlation between how many mm of rain the Blue Mts receives, and how much the Kelpie Point river depth gauge increases? I.e. if there's 20mm of rain in the area, how much would you expect the Cox's to increase.

Kelpie point is currently at 0.6m, with 20mm of rain forecast for Friday and 20mm on Saturday, or thereabouts, would this render it uncrossable on Sunday?

I crossed at Kelpie Pt when river guage was 0.28 in January this year. This is after the crossing - the deepest part was by the far bank left of centre... approx knee deep.

I'd take a couple of poles if it's still at 0.6.

We did K2K on 31 Dec 2020. Water level was 0.558 at Kelpie point. We crossed carefully and just made it without falling - luckily it wasn't 1cm higher!