The Water of Leith:  Past and Current

The Water of Leith: Past and Current

After heavy rain, it’s more than a kayaker’s playground. It’s also the council’s mission, a property-owner’s disaster, students’ soggy socks and an engineering marvel. The Water of Leith has been a temperamental feature of the Dunedin landscape; some days it’s Wind in the Willows, and other days it’s The Day After Tomorrow. Either way, the river has shaped some strange student traditions, and the University’s location.

Did you know where our main campus now sits used to be the Botanic Gardens? Because the river kept flooding the flower fields, the original gardens were relocated in 1869, and the city gifted the flood-prone land to the university.

Most of the time the river is more casual than a Sunday stroll, but by nature of its steep catchment (the area that catches all the rainwater is high up in the Waitati hills), large torrents of water can catch us down here by surprise. The biggest floods of the 1920s saw the laidback Leith turn into a roaring menace that cut down banks, overtook intersections, hollowed out bridges and caused more mayhem than a Hyde Street Keg Party. 

Over the years, a variety of construction works turned the river into a boulder-trapping, high-walled concrete channel complete with the double-laned drain that would be perfect for Thunder Road 2.0. Yet in times of heavy rain the Leith would still flood itself, and the Otago Regional Council took up the challenge of Extreme Makeover: River Edition.

The construction you walk around on your way to class is the latest in the engineering feats to tame the Leith. The Leith Flood Protection Scheme has been a decade long project (and counting) by the regional council. They are upgrading certain parts of the river so it can cope with a once-in-a-100-year flood. Through campus, the new Leith will be able to handle a flow of up to 202 cumecs (cubic meters per second); that’s 290 Olympic sized swimming pools flowing past the clock-tower every hour. Last June’s deluge saw the river at half that capacity, providing ripper rapids for kayakers and surfers. It also gave confidence that the protection works will do their job and keep the city streets safe.

The protection scheme was first rolled out in 2006 and is scheduled to finish in 2020, when hopefully most of you have graduated. Years of research and hydraulic testing helped engineers conclude that channel widening was the best improvement for the river, along with weirs (the steps) and more rocks. By increasing the width of the Leith at certain points, potential pressure can be lessened, reducing flow rate and the risk of flooding in the streets.

While the idea of paddling on your surfboard to class or being marooned at the flat sounds romantic, the novelty will probably wear off quickly. You won’t be able to pop into New World for supplies, the hospital might be tricky to get to and unless you have a wading suit, any outdoor activity will be soaking. If you live too close to the river’s edge, your house could flood and the carpet may reek for weeks. Transport services will be disrupted and could leave you stranded at university for a while.

Students aren’t the only creatures to live on the Leith. The river is home to a diverse range of slippery life: salmon, eels, brown trout, freshwater crays, and not to mention a plethora of insect species too numerous to mention. If you want to dabble in some fishing, you’ll need a licence from Fish & Game to catch ‘em all. We’ve all heard from a friend about their friend’s friend too poor to take out a fishing licence and caught a trout in his washing basket. Technically he didn’t use a rod or net so he got away with it, although it’s hard to imagine this being an easy method. With all the extra rocks and weirs brought in during construction come more niches for all the river critters. There’s a pair of Paradise ducks that hang out on the Clyde and Forth St bank; and if you’re an ‘I Spy’ kind of guy, try spot the camouflaged mother duck nesting next to the Leith St overbridge (hint: willow trees).

To preserve this biodiversity, construction work halts during spawning time of the fish, giving them peace and quiet to continue the circle of life. That’s why there isn’t much happening at the moment. But while you’re off enjoying the summer sun, the regional council will start construction on the Leith’s elbow bend, under the Information Technology Services (ITS) building. This is a crucial point on the river; if the once-in-a-100-year event hits tomorrow (don’t panic, it’s highly unlikely), this is where the Leith could overflow.

All the construction, rock moving and native planting is not just about making the campus beautiful, it’s also about keeping the city safe. While providing protection from the potentially risky river, the scheme has opened up the waterway and the improvement to the university grounds is an added bonus. Not many universities have a river running through their campus and an outdoor stage leading down to it.

Those new stairs outside St David’s were helpful for this year’s freshers of Selwyn College. Seventy-eight years ago, for reasons unknown, two Selwyn lads stole the Knox Master’s cast-iron bathtub and made their getaway by floating it back down the Leith. This set in motion an initiation tradition, the Leith Run. On the last Saturday of O-week, all the Selwyn freshers carry this heavy bathtub down the river, whilst being pelted with eggs, flour and unmentionables. This year’s initiation started at the Leith Street beach and finished on the stairs in front of the clock-tower. The old channel would have been impossible to scale, but now the Leith is the ideal place to take a break, a date, or even a bath for a run.

Another mysterious tradition is the elusive bike race. Students would crowd the overbridge and line the channel walls, again throwing allsorts at the tough souls carrying their bikes upstream. There is bare minimum information on this tradition, although photographic evidence associates it with the Capping Show of 1972. But who started it? Is it still going? Does that explain some of the dead bikes in the Leith? Did it happen this year? Who knows? But with the improved river bed the potential biking conditions are better than ever.

Students have been getting wet ‘n’ wild with the Water of Leith for years when it was as welcoming as The Wall. But now, thanks to the massive undertaking by the Otago Regional Council and the University’s Master Campus Plan it’s becoming an accessible, safer and good-looking river ready for action.

This article first appeared in Issue 21, 2016.
Posted 11:41am Sunday 4th September 2016 by Charlotte Panton.