Drainage, Heavy Rain, Climate Change and Home


Some years ago my wife and I downsized from our house and small acreage in the bush to a unit in town. The brick veneer unit was built in the 1980s basically to minimum building standards. In most instances these requirements and their construction have been sufficient. However in one instance – the drainage of roofs and surrounding pavement – inadequate construction has been evident for some time. Our first warning was that following thunderstorms the water spouted back up through the pavement drain instead of going down it. Also at the bottom of the downpipe beside our garage door a neat hole had been cut by a previous occupier to allow water to readily escape. This was to prevent water backing up the downpipe and overflowing the roof spouting and was obviously a reaction by the unit occupier to a previous event.

Action on this had been on my to-do list for some time but down my list of priorities. However some local flooding around a downpipe at our neighbours place required immediate attention to the problem. Outlet pipes were exposed and discovered to be blocked in several places and 2 incorrectly sited surface inlets that had disappeared under the turf over the years were uncovered. These deficiencies were fixed. But most importantly it became clear that the outlet pipes, even when functioning properly, were of insufficient size to cope with a prolonged heavy downpour. The inlet capacity was (and is) nearly 3 times the capacity of the outlet pipe for each unit. Clearly the standards for drainage of 30 years ago are no longer sufficient for today, not to mention that the drainage was both poorly constructed and designed.

Climate Change predictions for East Gippsland are that it will receive less rainfall and that the rain it does receive will be in fewer, but heavier, rainfall events – a recipe for flash flooding. It is fairly obvious that minimum maintenance is required for most of the systems that support our existence, something that is often neglected in this era of ‘privatising’ everything.  Likewise reactive politics (the status quo) often waits until something goes badly wrong before taking any action to solve or fix the problem. Planning to cope with a range of possible, but predictable, outcomes is nowhere to be found. Or worse still the status quo ignores or denies, for example, the fact that the damage from severe weather events may be climate change related and is thus unable to adopt mitigation or adaptation strategies. In the meantime we will observe whether our recent (and the previous) modifications will enable us to cope with the next heavy rainfall event.