Bushwalk Australia

Hello,

I've always been annoyed with the way the BOM reports river height data. As far as I can tell, they only make the last 4 days available, and their charting seems to have useless scales. See below for an example:


One gauge that I'm interested in is Coxs R at Kelpie Point. I wanted to be able to access historical records (so I could compare the current height to what it may have been a few weeks ago, or see when large floods or lows have occurred) and also plot it in a form that is useful.

I've therefore made a little script using google sheets which captures the data for this station twice a week, plots all records that have been captured. It also cleans the data a little by removing the large negative heights that occasionally appear.

I've also made a chart public for other bushwalkers that may wish to access it.


Let me know if you think it's useful. I only have a month or so data at the moment, but it should build up over time. If something like this already exists, I'd be all ears!

Alex.

Good work and interesting. I would think that Sydney water would have historical data in their records. It may be worth contacting them to see if they would make it public - a bit like the BOM have weather records public from various weather stations going back over the years.

You should also note that the Kelpie Point station is often off-line due to what City Rail would call "Operational Issues". I guess its hard to go in and repair these more remote stream gauges when they fail. Last time I was walking out that way - there was a tree across the road in one place and a small landslip at another place.

Yeh that'd be a useful exercise. Re the graph scale issues, I agree it's not very useful but you can view the data as a table, which if you really wanted you could copy into excel to make a more informative graph. As an aside, in terms of translating the height data to crossability (just made up a word), Sydney bushwalkers some time ago put up a link correlating kelpie point readings with how crossable the coxs was below Yellow Dog (see http://www.sbw.org.au/printed.aspx?active_page_id=476). Maybe we could establish something similar for this site, eg. a sticky thread that people could log qualitative info about crossings along with the reading from the relevant water gauge at the time (wouldn't have to be limited to kelpie pt/yellow dog/cookem etc.), to build a knowledge base that translates gauge readings into practical information and help inform decisions on upcoming trips etc. Just a thought bubble really.

Walk_fat boy_walk wrote:Re the graph scale issues, I agree it's not very useful but you can view the data as a table, which if you really wanted you could copy into excel to make a more informative graph.

Yep, this is essentially what I'm doing except on an ongoing basis. The BOM only have 4 days worth of data, wish it had more.

Walk_fat boy_walk wrote:Sydney bushwalkers some time ago put up a link correlating kelpie point readings with how crossable the coxs was below Yellow Dog

I'm not sure why the proper page disappeared, but it's good the 'printed' version still floats around on google. I could see if there's interest from the club in restoring the website and adding to it. I agree that having more data points and covering more areas would also be useful.

Allchin09 wrote:

Walk_fat boy_walk wrote:Sydney bushwalkers some time ago put up a link correlating kelpie point readings with how crossable the coxs was below Yellow Dog

I'm not sure why the proper page disappeared,

You may still be able to find the page .. on wayback machine. https://archive.org/web/ You'll need to know or guess at the web page address.

I was doing this for a while for the Colo at Upper Colo, but they changed the page format and my scripts started to fail, and I never got them updated. I was also capturing the surrounding rainfall gauge readings, as I was trying to correlate rainfall with when the Colo would actually start to rise for liloing.

One thing I found was that the base river height (the level that it would quickly revert to after rain) seemed to change over time. Anywhere from around 0.20m up to maybe 0.80m. Not sure why? You generally wanted about +0.30m-1.00m increase for good liloing. +1.0m-2.0m was probably going to be exciting, maybe dangerous. I went down there once at +5m, but bailed after a bit of paddling! Would have got from Bob Turners to Colo Meroo in no more than a couple of hours, but no chance of avoiding obstacles.

Why 2 day frequency? River heights rise and fall quite quickly. I'd be grabbing at least 3 hourly, and maybe even hourly.

I agree with you about the annoying lack of history and scaling of the BOM data!

Walk_fat boy_walk wrote:Sydney bushwalkers some time ago put up a link correlating kelpie point readings with how crossable the coxs was below Yellow Dog

I'm not sure why the proper page disappeared, but it's good the 'printed' version still floats around on google. I could see if there's interest from the club in restoring the website and adding to it. I agree that having more data points and covering more areas would also be useful.[/quote]

It got removed from the menus as there was too much clutter on the club's website. You can still access the page without the printed version - for now. The club is overhauling its website, so I imagine the current site will be decluttered further.
http://www.sbw.org.au/Content.aspx?active_page_id=476

The info would be more likely to be preserved if it was added to this thread (or another on the forum).

tom_brennan wrote:Why 2 day frequency? River heights rise and fall quite quickly. I'd be grabbing at least 3 hourly, and maybe even hourly.

Two day frequency?

BOM posts past 4 days of data so I thought capturing twice per week would cover the complete series. I wasn't so concerned about the possible delay of a few days, was intending to use it as more of a record than look at real-time heights. Guess I could make some changes to update the frequency.

Allchin09 wrote:BOM posts past 4 days of data so I thought capturing twice per week would cover the complete series. I wasn't so concerned about the possible delay of a few days, was intending to use it as more of a record than look at real-time heights. Guess I could make some changes to update the frequency.

Sorry, I misunderstood - capture frequency vs data frequency.

I see you're picking up all the data, which is fine!

Coxs @ Kelpie was up highest since I started recording last week, rose to 0.82m in a day from 0.05m

Looks like the data capture stopped working for about a year... but have just fixed it in time to capture this weekends downpour - Kelpie Point currently at 2.27m and rising!

Should give the Coxs, Kowmung and nearby watercourses a good flush out, but will be interesting to see if there's much erosion in the burnout areas

6.14m at 5.31pm today!

The Wollondilly was pumping this weekend. Thought about crossing it....then thought, Nah looks filthy.

You should also note that the Kelpie Point station is often off-line due to what City Rail would call "Operational Issues". I guess its hard to go in and repair these more remote stream gauges when they fail.
Kelpie Pt must be one of the easier gauges to get to. And they have such a nice fishing lodge there too.
Oops - sorry: 'emergency crew shelter' . . .

Cheers
Roger