Water

Sliding Scale

10   0
30   6.93
55   11.11
80   14.32
81   19.31

Over the last two months, we have received numerous queries from residents questioning their water consumption. From feedback gathered to date, many don't realise the amount of water they potentially use on their landscape. We have requested resident landscape contractor, Mark Atkinson, to provide information to residents to better understand and control their landscape water consumption. Please email him should you require assistance - prohortcc@vodamail.co.za.

What you need to know about your water consumption

Almost weekly I’m asked how it’s possible to accumulate such high water accounts.

The Facts:

• The larger your garden, the more water you use.
• All new gardens need more water, until they are established, even if these are considered water wise gardens.
• If you have a garden, it will consume 55-85% of your total monthly water consumption.
• 1 Kl (Kilolitre) = 1000 Litres or 1 cube (m³) of water.

Understanding the basics

A correctly designed irrigation system in Val De Vie, should be using between 1500 (minimum) & (absolute max) 2500 litres / hour. I say ‘correctly designed’ because if a system is running at the right operating pressures in Val De Vie, this is what it uses in an hour. The water used per zone, is dependent on the number of sprinklers / pop-ups on a given zone, and their selected nozzles and required operating pressures. If a zone is using more than 2500 litres / hour, it’s most likely running at the incorrect pressure, if less than 1500 litres / hour, in time, materials will be damaged due to high operating pressures.

With this in mind, I’ll use my garden as an example as to how much an irrigation system uses. I have 9 zones (stations) in my garden. On average these use 1.87 m³ / hour – in other words - 1870 litres for every hour it runs. If I run each zone for 10 minutes this equates to (9 x 10 mins = 90mins or 1.5 hours) Therefore, every time I water my whole garden, I use 2805 litres of water. If I water everyday this equates to: 2805 litres x 31 days (or however many days in a given month) = 86 955 litres in one month (86.95 kl) My total water consumption for December was 116 kl – therefore my irrigation system used 75% of my total water consumption for the month. Some homes on the estate have as many as 16 zones, watering 15-30 minutes a zone, regardless of whether or not the garden needs this much water.

Using the above calculations, you’ll easily work out just how much water your using for your system; this could equate to: 14 950 litres / day or 448 500 litres / month (over 30 days). That’s 448.5 cubes of water a month, or imagine 448.5 bakkie loads of water!!! Consuming this amount of water is in fact illegal. Don’t take 10 minutes as the standard for all your zones, some zones require 20 minutes of watering time, to water the area efficiently, If you’re not sure, get advice.

Once again, my garden has been prepared correctly to sustain minimal watering. My irrigation system is designed efficiently to cover areas correctly, and when I see things are dry, I often need to do a manual watering, sometimes I water only the zones requiring water, not just simply everything. I’m constantly monitoring my irrigation system. Initially a new garden needs to be watered every day.

Other factors influence how much water is required; these include:

• How the garden was prepared - related to how much compost or organic material was introduced to hold water.
• Where the garden is situated on the estate: The Village area is predominantly sand, with little holding capacity; resulting in more frequent watering. Areas around the Dams are predominantly clay based, these areas hold water well, however overwater results in run-off and erosion and waste. Areas bordering the farms are saturated with rock pebbles / boulders; once again with little holding capacity.
• Weather conditions & exposure to these elements – For instance, properties around the dams and polo-fields generally receive constant winds, drying out the plants, unlike the more sheltered Village areas Many homeowners turn on the controller, and forget about the irrigation system. It continues to water, everyday, regardless of whether or not it needs to. As consumers of water, we need to be more responsible and aware, otherwise you’ll pay. This is precisely why the municipalities introduced the water sliding scale tariffs. What can you do to reduce your water consumption.
• Be aware and monitor your irrigation controller & system requirements.
• Monitor your garden, sometimes the top layer looks dry, but below the surface there is sufficient water. As the garden grows, it should require less water.
• MULCH your garden with plain coarse compost – NOT BARK CHIP.
• Water during the early mornings, not in the heat of the day. In winter water a little later in the morning (6:30 onwards) to avoid frost damage.
• Install the best irrigation system you can afford, a poorly installed system cannot be managed or run efficiently, (I’ve seen loads of irrigation systems on the estate where the water is atomizing under the pressure); if installed poorly it will cost you more in the long run.
• Enquire as to whether your irrigation controller can accommodate a rain sensor. These are relatively cheap, and save water.