I recently snuck off from a social tramping trip to the Copland Hot Pools to make a solo ascent of the West Ridge of Mt Sefton. The easiest route on Mt Sefton (MC 2+), the West Ridge provides a straightforward snow climb from Welcome Pass. The route either follows the reasonably level Douglas Neve to where a final snowslope leads to the summit, or else a much more interesting and crevasse free option involves gaining the ridge crest shortly after Welcome Pass and sidling a beautiful sharp snow ridgeline until the final summit slope. Without a friend to pull me out of a crevasse on the glacier, that's the way I went! Setting off from Welcome Flat I made good time to a bivvy on Welcome Pass, from where I climbed Sefton the next morning before returning to the hot pools for a late lunch.
From Welcome Flat Hut cross the swingbridge and follow the track towards Douglas Rock Hut. After a short section of bush 40 mins from the bridge, the rough floodplain created by Scott Creek is reached. Leaving the track, follow Scott Creek, boulder hopping and crossing the creek as necessary to the 600m contour, about the point where the true left of Scott Creek becomes a bedrock bluff. Opposite, on the true right, a large cairn on a terrace 10m above the river marks the start of the 'Bluewater Route,' a rough track cut and marked by hunters in the past few years. The old route up the Scott Creek waterfall is now massive eroded waterfalls, so forget about it. The Bluewater route is great - if you have time, take flagging tape and a folding saw and help keep this excellent route viable.
From the terrace, the track heads down-valley in the bush for a few minutes, crossing a wee creek (marked on the map) before climbing a moderately steep bushy spur. Once you find the track it's generally easy to follow, with plenty of flagging tape and a good ground trail in places. The odd bit of windfall might have you spending a few moments looking for the next marker, but it's fine. There's water at the bottom of the track and at the 800m contour. At bush line, the track continues through the scrub, but the flagging tape isn't as abundant (if the Dracophyllum branches are neatly sawn off, that might be a good indication you're still on route...). The trail gains a spur with a few rock outcrops (obvious from above, when descending) and peters out at about 1260m, where the route now sidles right 100m to gain a tussock spur that leads to some prominent bluffs. Abundant thar and chamois in the area have left strong trails at the base of the bluffs which are followed into a basin (left, looking up) below Pt 1784 and Pt 1800. From the basin climb to the saddle between Pt 1784 and Pt 1800, drop off 20m on the Tekano side and climb up to Pt 1800. From here follow the obvious ridge crest dividing Scott and Tekano creek to the 2000m contour. From here, sidle broad easy snowslopes to Welcome Pass. This traverse gets nailed by afternoon wet slide avalanches in spring and has crevasses from early summer - roping up for glacier travel is prudent once the slots start opening up. If the crevasses aren't open, then speed is safety (to avoid avalanches). Welcome Pass has plenty of flat snowy ground for tents and a few rock outcrops for those in bivvy bags - I landscaped a lovely wee ledge for one at the height of the Pass, 50m on the northern side. A few patches of melting snow on bluffs gave me running water at the pass, but this was during very warm weather.
From Welcome Pass, drop a few m to the Douglas Neve and follow it either as far as you can (avoiding crevasses) before eventually climbing to the West Ridge at a flat area at ~2800m (about where the North Ridge coming from near Douglas Rock Hut meets the West Ridge). The ridge crest option follows the Neve for 10 mins before climbing a big easy snowslope to about Pt 2602. From there the ridge undulates and meanders until the flat area at 2800m. Don't climb immediately from Welcome Pass - you'll end up on a wee summit that goes nowhere. The exposure is pretty big and in a few places one sidles (whatever side of the ridge looks good) on up to 55˚ snow. From the 2800m flat area it's straight up a bleedingly obvious summit pyramid with snow up to 40˚ - this can on occasion be bulletproof ice, and as a result has been pitched even by competent parties. Looking up you can tell that there are two summits at a similar height. The left hand one is easy, the right hand one has an annoying step in it, but fortunately they're both at the same height so no worries, take the easy left hand one!
There isn't any technical ground on this route, but parties anticipating crevasses (after ~late November) or concerned about possible hard ice on the summit pyramid could take one half rope, one or two snowstakes, and a couple of ice screws. Anything above a stiff tramping boot would get the job done - fancy gear isn't needed on this technically straightforward climb. Two ice axes were handy for the steepish snow on the ridge - if you're determined to go light, in good snow, confident climbers would probably get away with one axe but this wouldn't be as comfortable.
Avalanche gear? Hmmm, in my opinion if you get nailed by an avalanche sidling the Tekano Neve, forget it man, you're toast. You'll get pushed over some mega bluffs. Better to go light and move fast? Up to you. Serac collapse threatens the Douglas Neve so same rules apply if you are taking that route. The objective danger is low once on the ridge itself, but watch for cornices.
GPS is very handy for navigating the route to Welcome Pass as cloud can hang around from bushline in the afternoon even in fine high-pressure weather.
Bivvy bag/tent, jetboil, usual bivvy clothing. Take 2-3L of water carrying capacity as there is no reliable water between 800m and the snowline. I found water in the basin at 1500m (due to snowmelt) but this disappears later in summer.
Welcome Flat Hut-start of the Bluewater Route in Scott Creek: 1.5-2 h. To bushline: 1.5h. To scrubline: 1-1.5h. To the saddle between Pts 1784 and 1800 1.5-2h. To Welcome Pass: 2.5-3.5h.
To summit of Mt Sefton from Welcome Pass: 2.5-5h, return 1.5-4h.
From Welcome Pass to Welcome Flat Hut: 5-8h.
For reference I got to Welcome Pass in 8h, climbed Sefton in 2.5h, descent back to my biv was 1.5h, and I took 5h to get back Welcome Flat Hut. The descent was fairly fast with good snow down to 1500m, the terrain below Pt 1800m would be slower without snow.
For all photos go to https://jazmorris.smugmug.com/Mountaineering/Southern-Alps-NZ/Mt-Sefton-...
For more beta on the Bluewater Route go to http://climbnz.org.nz/nz/si/main-divide-of-the-southern-alps/mt-sefton/b...