Canary in the coalmine

Last week Lake Omapere erupted into a frothing mass of blue-green algae. A stink enveloped the lake and surrounding area, eels and other creatures were dying en masse, and it became dangerous to even swim in it, let alone drink it. This is a huge indictment on the state of environmental management in Northland. We are failing in our duty to protect, and even worse, think that more of the same is going to produce a different result. I think Einstein defined this as madness; thinking this problem is going to go away certainly is.

At our last council meeting I quizzed the reporting officer as to the exact cause. Sure, high temperatures and windy weather had pushed it over the brink, but they were exacerbating rather than causal factors. The problem lies with the lake’s high nutrient levels. Being so shallow, wind can stir up the nutrient-laden sediment from the bottom, and when the water temperature gets up, bingo! We have an environmental disaster on our hands.

Lake Omapere is the canary in the coalmine. It is highly vulnerable, and serves as a warning that we need to get our act together.

We have learnt that wetlands and riparian fencing are effective methods of reducing the flow of nutrients into waterways, and it was mentioned at the council meeting that significant riparian planting had been undertaken around the lake after the last algal bloom in 2003. A quick check via Google maps showed there were still huge gaps around the lake, and most of the small waterways that carry high nutrient loadings were still accessible to stock. So there’s room for improvement.

The big question, of course, is who is going to pay for it? Here’s an idea. We know that manuka is likely to be the best plant to absorb nitrogen runoff, and it kills off E. coli. It is also a very valuable crop, producing medical-grade honey. Lastly, Shane Jones’ Provincial Growth Fund has amongst its targets the planting of one billion trees, including natives. (Additionally, Mr Jones is keen to get his ‘nephs’ off the couch and out to work.) It doesn’t take a rocket scientist to see that with the right leadership we could see the bee industry partnering with farmers, iwi and the NRC, supported by a contribution from the PGF, to plant the huge amount of manuka needed to effectively protect Lake Omapere from nutrient runoff. The multitude of nephs needed to plant (and fence off) the hundreds of thousands of manuka seedlings could then be trained as beekeepers to harvest the fruits of their labour.

Farmers would benefit by an income from the honey, carbon credits from the trees to offset their agricultural emissions, and guaranteed clean water for their families and livestock. If that’s not a win-win-win, what is? mikef@nrc.govt.nz

"Lake Omapere is the canary in the coalmine. It is highly vulnerable, and serves as a warning that we need to get our act together."