For the second phase of the expedition we dropped down to six people for a few days poking around the Ōpārara River, one of my favorite karst areas in New Zealand. With some difficulty I managed to navigate the red tape to secure us the necessary permits for us to stay at the Honeycomb Hut to explore and map caves nearby, and also a permit to be able to do a couple recreational trips through Honeycomb Hill Cave. We started based in Karamea with a day along the lower Ōpārara River at the Fenian Track (Fenian Day 1). A DOC loop track off to the side guides trampers to three very different caves (Miner's, Tunnel, Cavern Creek) and includes a mandatory traverse of Tunnel Cave from submergence to resurgence. Despite the high visitation, no one has ever bothered to survey these caves, which I thought was a worthy goal. I had scouted the caves a couple years earlier and even partially surveyed Miner's Cave. I sent Carl, Jed, Carol, and Joel off down the trail to survey the Fenian Caves while I recruited Mark to join me on a potential bush bashing goose chase. I spotted what I thought should be a well-defined ridge in the lidar, and despite the likely thick coastal bush, wanted to see if I could establish a route up to the granite/limestone contact above the parking lot.
After some difficulty finding the ideal place to dip into the bush, we passed through a lovely nikau palm grove then began the steep climb up the hillside, using our hands as much as our feet. Eventually this got us onto a ridge where travel was much improved. It took us about 45minutes to go 500m horizontal and 200m vertical, but frankly I could have made half that time if I went solo so I considered this a success. Once we arrived at the edge of the limestone though the travel actually got much worse with some terrible windfall, jail bar-like supplejack thickets, and even some bush lawyer thrown in for good measure. Slowly we worked our way east along the granite/limestone contact, discovering some very interesting resurgences and submergences along the way as the water curiously followed the contact to the east instead of just plunging southeast down the contact. We documented several interesting features, but none that were obviously more extensive. With the slow progress we only made it about 400m along the limestone to an entrance that had a faded venetian blind tag on it (AR 132), a sign that the Buller Caving Group had been to this area in the 1980s. We stopped 100m short of the minimum I was hoping to get to, worried about the time it would take us to get back through or around the windfall. We tried a steeper descent more directly down to the trail that had some exposed root-clinging sections down active landslide scarps, a route I would not opt to ever do again. Once on the trail it was a short stroll back at least.
Meanwhile Carl put in a stellar effort in Miner's Cave where I had left the survey at a low and wet crawl (no air in the high water conditions I saw it in). He pushed through to find quite a bit more cave, eventually getting through a miserable muddy squeeze into a large but brief borehole passage on Cavern Creek. It is quite possible that despite the generations of high visitation to this cave that he was the first to make a throughtrip. Meanwhile Carol and Joel put some effort into mapping Tunnel Cave and noted that this too seemed to have extensive passages with minimal visitation. After the bust of Garibaldi Ridge, I think everyone was happy to actually get in a cave today! We decided to end the day in Karamea one last time, then drive on to the Ōpārara Basin in the morning.
In the morning (Ōpārara Day 1) we set out for the McCallums Mill Road end. We packed for the 1 km to Honeycomb Hut and got ourselves situated at the always cozy hut. The hut could sleep six with bunks in two rooms, but Jed and I opted to each pitch a tent outside to free up a little more space. I sent Carol, Carl and Mark to survey AR 102, a nice 100m throughtrip near the Ōpārara Arch that I rediscovered the hard way a couple years before, finding it from its upper entrance after a lengthy bush bash only to find it was tagged on the bottom entrance. I led Joel and Jed along the cut track and then off north of the Ōpārara's big bend to an area both Neil and Kieran separately suggested there was a cave worth surveying. The Ōpārara was as low as I have ever seen it and I could actually cross it with dry gum boots the whole way up. At one point we spotted a very chill male/female pair of blue ducks paddling around, which was a nice thing to see.
The most obvious caves were two entrances under a limestone dripline on the true right margin of the river so I started surveying while Joel and Jed had a look around. This ended up being two hyper-sinuous canyon passages, both making throughtrips through the block of limestone. By the end of the survey I had to assume this was not the cave they had in mind; it would be borderline insulting to send me to map it. On the way back we checked out the interesting karst window only 100m north of the hut. I had previously checked out the terminal submergence but the resurgence was actually a very nice section of stream passage with 180m of walking/stooping through beautiful sculpted limestone; curiously this stream lacked the tannins in the Ōpārara River nearby, had nearly as much water, and flowed away from the river suggesting a separate, more mysterious source. I later ended up calling this the Rogue River System to emphasize its mystery. Back at the hut I text messaged Kieran on the InReach trying to get more info about the cave he wanted to send us to.
The next day (Ōpārara Day 2) was our Honeycomb permit day so I led two trips through the cave to adhere to the permit stipulations regarding group size. Both times we went A to L entrances on the tourist trail, up the Honeyflow Stream to the T entrance, then back down the stream, then Bee's Knees, Eagle's Roost, Hives Canyon, Gypsum Passage, D Canyon, D Passage, Winter Garden, out the M entrance then through the Honeycomb Hill Arch. My usual plan of continuing down the Ōpārara River was thwarted when it was clear there would be mandatory swimming instead of shallow wading. I managed to find an easy enough escape up and across the top of the limestone wall, finding another marked cave, AR 115, in the process. From here it was a straightforward jaunt back along the cut track back to the hut. Both groups enjoyed the many entrances, defiantly large moa bones, and nice patches of glowworms. Carl and Jed surveyed the Rogue River submergence (35m) and resurgence (188m) pair near the hut in the morning and then I took them for an afternoon tour through Honeycomb. The following photos cover the pretty typical highlights from a Honeycomb Hill Cave trip.
A flurry of texts from Kieran came through on my InReach the previous morning including some lat/longs for some caves to survey so we had more tasks to do for Ōpārara Day 3. Carl and Mark tackled the upstream extensions of the Rogue River System in a cave they ended up calling Mud Lover's Delight, then Carl surveyed AR 115. Carol and Jed explored and surveyed two additional caves nearby. Joel and I headed back up the river to Pt 294 now that we had a GPS location for the cave Kieran wanted us to survey. With the GPS point Kieran only offered "Decent cave. Needs surveying" for a description. Thus, before we had even visited this cave, this cave became named Decent Cave, and the cave I surveyed the first day across from it in error retroactively was named Indecent Cave (145m). Joel and I found Decent Cave immediately (white tag too faded to recover a designation) and surveyed it without issue. It was a straightforward single passage that went in 129m to a sediment choke so "decent" actually seemed a little generous. The most interesting feature of the cave is that halfway through the cave ceiling becomes the siltstone overlying the limestone so the cave developed right at the upper contact; the siltstone had all sorts of pectin fossils to add to the appeal. This survey did not take us all that long and so we did some exploring on the true left of the Ōpārara past the big bend in the river, finding some interesting bits and pieces but no system of significance. As we got close to the other teams, Joel found an interesting entrance with a strong draft coming from a brief knee crawl and so in we went to pop out in a slot on the other side. Up the slot Joel disappeared into a subtle entrance, eventually finding footprints and realizing that this was the back side of the cave Carl and Mark surveyed (Mud Lover's Delight). Just inside the entrance was the largest moa bone I had ever seen, thoroughly impressive. I checked out an additional third entrance on this slot and then we both walked out of it to find ourselves right at the Honeycomb Hill Arch. On our walk back we ran into Carl who had just finished surveying AR115 (81m)- prefect timing. Carl saw a great spotted kiwi after dark, which I was mildly jealous of.
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| Decent Cave |
For the last day in the area we had a split target of both Ōpārara and Fenian. Carl and I rallied for an 8am start to head back to the caves in the rift past Mud Lover's Delight; we did a surface survey to connect to the throughtrip cave. At a weird pit drain feature Carl noticed that the two caves were ridiculously close with a side passage in Mud Lover's Delight. I practically moved two small rocks and there was the hole connecting the two! I looped around into Mud Lover's and we managed a handshake connection between the two which was very satisfying. With similar motivated effort we managed to connect the throughtrip section to the next passage to the north, giving Mud Lover's Cave 4 entrances and 275m of surveyed length. Carl and I were both thrilled at the productive morning and were motivated to do more with the day. We packed up, locked the hut, rejoined Mark at the car, then drove around to hike the Fenian Track in to map Cavern Creek Cave (Carol, Jed, and Joel left earlier to hike in and work on Tunnel Cave. Carl and I were nice and productive, wrapping up the survey of Cavern Creek Cave (really two caves totaling 143m) in about 2 hours. Thankfully it was overall less wet than I anticipated. Meanwhile there was all sorts of shenanigans with Mark walking off the track and up the creek, Jed looking for but not finding the Fenian Workings, and Carol and Joel making a little progress on Tunnel Cave but not finishing it. I ended up running the entirety of the cave loop track to make sure I flushed them out (they must have already started hiking back down the track). This was one of the more satisfying days of the trip for me, largely thanks to Carl's company and motivation. Onward we drove to Westport for groceries and dinner, then a moderately late arrival into the Charleston Cave Base were we met up with Henry, Travis, and later Kieran. The subsequent blog post describes Charleston.
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| Cavern Creek Cave |
While in Charleston the fact that we had not finished mapping the Fenian Caves despite the involvement of seven people and three days of surveying, really festered inside me. This would be one of the more useful and tangible products we could provide to DOC to document frequently visited caves and I did not want to leave it incomplete. I really really wanted to finish the survey of Tunnel Cave and frankly at this point I only trusted Carl and I to complete it. Carl was keen and so we rallied hard with a 6am departure from CCB to get us all the way back up to Karamea and the start of the Fenian Track. We dressed and packed for speed, making it to the upper entrance of Tunnel Cave in about 45 minutes. We cleaned up a few leads and corners, surveyed the lower side passage to the secondary entrance, then the extensive northeastern side passage through some very decorated and surprisingly minimally trodden galleries, then finally I dug open a small extension to the north that obviously would have continued to an additional entrance (draft) but had a formation choke. In all we made great time wrapping up Tunnel Cave while adding lots of survey. We sat in the upper entrance eating a snack while we waited for the rain to subside.
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| Tunnel Cave side gallery |
When the rain finally did subside we found that we still had more day left (despite inevitably needing to hike out and drive two more hours back to Charleston. Going further along the limestone contact seemed pretty unpleasant in the wet bush so instead I suggested we detour off the track downstream on Fenian Creek to where lidar suggested some odd topography where it encountered the limestone. We followed a [currently dry] overflow channel to a limestone cliff, and sure enough a cave with water below. After a little clambering around we found a more obvious way into the cave, dropped packs and explored surprisingly pleasant multi-branched flood maze passages. The limestone was beautifully stylo-bedded and crisply sculpted throughout. In short order we found at least 4 entrances, with at least four points where Fenian Creek was pirated through the limestone. The dramatic bottom resurgence entrance popped out right at the contact with the underlying granite in a lost world window with both upstream and downstream rapid-filled slots on the river. Back at our packs Carl and I looked at each other, acknowledging the time but also drawn to the allure of mapping a great little cave on the spot. We surveyed as efficiently as we could, while still check out the many nooks, crannies, and drainage pipe passages this cave has to offer. While not officially one of the tracked Fenian Caves, it makes for a very worthwhile detour for both cavers and trampers as long as the stream is not running high. By the time we finished mapping the stream had come up a little more and there was now water starting to flow down the overflow channel.
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| Fenian Flood Maze Cave (and below) |
This last day was as good as the expedition got for me personally. It was the only day I was really challenged to push, be productive, and to map a functionally new cave. Once again Carl was MVP. It was also a nice reminder of the value of lidar in being able to find new caves, even those 50 m off of a DOC track. The Ōpārara remains a really intriguing area for me, one that I would love to spend weeks of my life exploring in intimate detail.
