Know How Stormwater Pits Work

1. HOW STORM-WATER PITS WORK New Zealand is lower south than we are, but it’s a much smaller land mass and has a diferent climatic pattern than we do, so it’s much wetter and greener. Either way, a combination of our low rainfall (the wettest Aussie spaces only get 600mm of rain per year) and large central deserts mean we don’t rank high on the greenery scale. That said, when it does rain, it rains hard. And because most of us live within 50km of the coast, there’s a large risk of fooding. The people that designed urban Aussie spaces were aware of this. GET THE BASIX RIGHT Still, even in places that are well within construction guidelines, the rainy season can easily overwhelm municipal waterways. That can lead to soil erosion, sinking buildings, and millions in property damage. So as part of Basix building rules, new homes must contain green infrastructure, lower emission features, water tanks, and detention tanks. The latter are storm-water solutions intended to reduce the harm done by excessive rainwater. Because while tanks can collect water for use, they can only hold so much. CALL IN THE PROFESSIONALS Storm-water pits are designed by water engineers and built by plumb- ers. They’ll do careful calculations based on building size and soil type, determining the right size of storm-water tank for your property. They usually have large grates at the top to let water in while keeping larger debris and small animals out, because these could cause a blockage and make the fooding even worse. The system is designed so the inlet is much bigger than the outlet. This means your storm-water pit receives rainwater en masse but releases it more slowly.