flood control

Wairau River – ancient and modern engineering

envirohistory NZ6 Comments

Plan of lagoons and channels dug by Maori at the mouth of the Wairau River, drawn by J.L. D'Arcey Irvine. Alexander Turnbull Library, MapColl 832.2gmtb [pre-1840] Acc. 120
Plan of lagoons and channels dug by Maori at the mouth of the Wairau River, published by W. L. Skinner in 1912. Alexander Turnbull Library, MapColl 832.2gmtb [pre-1840] Acc. 120
In 1963, a major engineering feat was completed on the Wairau River, in the Marlborough district: the Wairau diversion.  The diversion created two Wairau Rivers, one following its original course, which meanders south-east into a network of lagoons, before reaching Cloudy Bay at Wairau Bar. The “new Wairau River” was a channel that connected the river through a cut eastwards to the sea. Continue reading →

What is a groyne? (And what’s it got to do with environmental history?)

envirohistory NZ4 Comments

Living in Christchurch, I was always vaguely aware of a park in the north-east of the city called “The Groynes”. It seemed an odd, and rather un-illustrious name for a park (given its homonymity with that particular part of the body), but I never took the time to find out what its origin was.

Had I had the curiosity to investigate, I would have found out that “The Groynes” derives its name from large blocks, made from concrete filled woolsacks, which were placed in the Continue reading →