Page last updated 13Jun14

River Crossing

With my thoughts turning to crossing the Eucumbene and Murrumbidgee Rivers at the end of the snow season on the October long weekend, I fortitously came across an excellent article on river crossing in Wild #119. It’s by Whitney Thurlow, the Director of Aspiring Guides in Wanaka New Zealand. Check out the web site – the place to go if you want to climb, walk or ski in NZ. Anyway, a quick email resulted in his ready response giving me permission to summarise and publish his advice.

1. the most important question – if I lose control and are swept downstream, is it clear of serious rapids, rocks or snags? If not, search for a better crossing, wait for water to go down, turn back
2. is the river crossable – generally, if you can see the bottom and it is less than knee-deep all the way (water deeper on outside of bends), ok. If water deeper, needs to be slow moving so you can maintain balance. If can’t see how deep, take further precautions
3. preparation – secure all techno-gadgets (my term) – camera, GPS, PLB; pack will float, so keep it on; if alone, use a strong support such as a strong stick – test that you can lean heavily on it without it breaking; use on upstream side as a crutch to maintain 2 points of contact at all times
4. GROUP CROSSING – stand side-by-side, largest person upstream end; stand close together; slide arms between pack and back of person on either side, wiggle arm until can grab the pack strap on the far side of your neighbour (will need to loosen your pack, as will have arm of person on each side of you reaching around your back); this forms snug line and if one stumbles they are supported on either side; talk to each other, shuffle slowly across; if water becomes too deep or line unstable, slowly retreat
5. what to do if swept away – float on back, head upstream; pick which side of the river you want to go for; position self at 45° to current; kick legs hard and do fast backstroke.

Let’s hope I don’t have to try it!

In March 2014, the Canberra Bushwalking Club conducted river crossing training. See here.

Weather

Bureau of Meterology for Canberra: http://www.bom.gov.au/act/forecasts/canberra.shtml
WeatherZone for Canberra: http://www.weatherzone.com.au/act/act .

Walk Timing

“Naismith’s Rule – for an average walker with a medium pack, allow

1. 1 hour for every 4km of easy going; 3km of easy scrambling; and 1½km of very rough country, deep sand, soft snow or thick bush. Then
2. add 1 hour for every 500m up, and 1 hour for every 1000m down.

For very fit and experienced walkers reduce the total time by one third, and for larger, less fit or less experienced groups, this rule may be optimistic.” (Bushwalking and Ski Touring Leadership, Handbook of the Bushwalking and Mountaincraft Training Advisory Board Inc, 3rd edn, 2000)

Rough guide for planning:

Track 12 min/km 5km/hr
Open scrub 20 min/km 3km/hr
Medium scrub 30 min/km 2km/hr
Thick scrub 40 min/km 1.5km/hr
Rock hopping 30 min/km 2km/hr
Steep slope add 5-10 min/100m climbed

(Finding Your Way in the Bush by George Carter, Walk Secretary, Canberra Bushwalking Club, rev Apr 1993)

Temperature Variation with Altitude

The ambient air temperature decreases by about 1°C (perhaps 3/4°C) for every 100m climbed. More exactly, with little humidity it decreases by 0.98°C/100m and at 100% humidity (eg. in rain, snow, cloud) it decreases by 0.6°C/100m – see here .

Wind Chill

The increase in wind chill approximates the square root of the wind speed. Try the calculator here .

Daylight Hours

Use the calculator here to calculate daylight hours. For example, useful walking limits would be from beginning of morning civil twilight to end of evening civil twilight. Don’t forget to specify daylight savings, as appropriate (see below), by selecting Australian Eastern Summer Time (EDT) as the Time Zone.

Daylight Savings in the ACT

From the beginning of daylight savings in October 2008, the ACT will align its daylight savings with NSW, Victoria, South Australia and Tasmania. It begins on the first Sunday in October at 2am – put clocks forward 1 hr; ends on the first Sunday in April at 3am – put clocks back 1 hr.

Corin Dam Holdings

Graph here to see current Corin Dam holdings.

Useful additional maps

1. Bimberi Nature Reserve Draft Fire Operations Map http://www.environment.nsw.gov.au/resources/parks/FMS_bimberi_draft_operations.pdf
2. Lower CotterCatchment Recreational Zoning June 2009 http://www.tams.act.gov.au/__data/assets/pdf_file/0006/148353/Recreation_Zoning_Map_Jun09.pdf .

NSW Park and Fire Management Plans

See http://www.environment.nsw.gov.au/parkmanagement/ParkAndFireManagementPlansByCategory.htm . This is a useful reference for maps, tracks, background to various areas.

ACT Bushfire Operations Plan

See http://www.tams.act.gov.au/play/pcl/fire_management/2010-11_bushfire_operations_plan . This page has links to ACT fire trail maps.