It is critically important we all prepare for the next extreme weather event by undertaking some simple actions to avoid unnecessary flooding in our streets and homes.
Over the past 18-24 months, severe storms at times have far exceeded the Auckland drainage network’s capacity, so your association has sought advice from Auckland Council about how to keep overland flow paths functioning, and therefore prevent water entering your homes.
Catchpits, strip drains and gutters
Blocked drains and gutters increase the amount of water flowing over the ground surface during extreme events. There are many factors that increase the impact of flooding.
· Everyone should regularly clear their gutters and drains on the surface such as catchpits (gutter drains) and strip drains at least twice a year. Gutter drains, not on the road, but those in shared driveways, are the residents’ responsibility to maintain or keep clear.
· Keep lawn clippings and other vegetation clippings away from places that could be washed into street or private drains during rain events. By doing this you will help to ensure overland flow paths are not blocked or water doesn’t pool up or flood in locations it shouldn’t.
· Auckland Council has increased the numbers of contractors now carrying out maintenance (clearing) drains on public roads, and aims at checking all these drains twice a year. If you see a blocked drain, report it to the council by ringing 09 301 0101. The council aims to respond to those blockages within 10 working days during dry weather but will aim to respond to flooding gutter drains during weather events in two hours.
· You should also contact Auckland Council if you see that debris is blocking large areas around gutter-drain grates.
Your house should be above other ground levels
Don’t build up soil or create paths that make the section level the same as your house. Do this and water could flow through your house in a storm event.
· Make sure you always 'step up' into your house. This will help to ensure water will flow past your house and not into it. There is a temptation to landscape your section so you can walk from your section or car into your house on the same level without needing a step.
· Keep obstructions such as planter boxes away from your front door. You don’t want these items diverting water into your house.
Fences, overland flow obstructions and driveways
During a storm event it is critically important, and also a property owner responsibility, that water is able to continue its natural flow. Put simply, you must keep the overland flow path clear. Examples are:
· Keep a gap below a fence so water can flow underneath it.
· Historically, driveways had ‘humps' at the property entrance that kept water flows from entering properties. Many people didn’t like having to drive over humps, so they removed them, allowing flood waters to access their land. This is not a good idea.
· Keep your property clear of materials that could be picked up by flood waters and create a blockage leading to damage to your home. Check whether your landscaping, any loose material or any outbuildings such as garden sheds could cause blockages.
· If you live in a flood plain, it is illegal to stop or divert the water flow through your property by creating what is known as a ‘dam'.
For example, a dam would be building a concrete block wall to prevent water’s natural flow through your property by diverting it to your neighbour’s property.
Other recommendations from Auckland Council
If you are in a flood area you should:
· Store valuables and important documents in high places.
· Ensure that areas that might flood such as garages and basements are not used for sleeping.
· When landscaping, make sure the ground is shaped to direct water away from your home.
· Where possible, use materials that allow water to drain through them, like grass and permeable paving, instead of concrete.
· If you have a stream running through or near your property, keep the stream free of debris and plant stream banks to reduce erosion. Choose native plants that lie flat or have narrow trunks to allow water to flow freely.
Auckland Council Flood Viewer
You can see whether you are exposed to a flood hazard by studying the Auckland Council’s Flood Viewer,
www.aucklandcouncil.govt.nz/floodviewer If you click the 'Learn More' button on each of the types of flooding, there is text about actions that can be taken at a property level.