We all know that water is a precious resource and an ever increasing cost element. Being water wise makes financial sense. PMD includes rainwater metrics as a standard addition to our LTMP (long-term maintenance plans)

An extract from a recent LTMP :

Average maintenance cost equals R 66000 per annum.

The cumulative rain water funneled through the storm water drains equals 3703kl  and value R 103 678 per annum

  • Catchment areas (roof 60% and tarred roads 40%) feeds into the storm water drains
  • Water value calculation based Cape Town municipality on R/kl tariff  and 0.91 runoff coefficient

What does this mean?

You do the maths!

Quick considerations on rain water  harvesting

  • Catchment Material – The material of the roof is not as important as contaminants that may be on the roof – Roofing containing lead should be avoided. Cementious roof tiles is suitable for drinking water replacement. whilst metal sheeting  and roads are suitable for landscaping
  • Direct gravity feed : Establish gutters and direction to guide and capture your rooftop water directly to storage tanks. 
  • Redirect water pumps: Redirect water from circuit to storage tanks
  • Capture: Debris/leaf catcher/filter should be fitted to the source and overflow system should be installed at each catchment base.
  • Collection: A cistern or storage tank can be as simple as a rain barrel to a more complex array of tanks. 
  • Storage: Can be a central reservoir or a network of linked or standalone tanks
  • Usage:  Simple gravity feed system  or high pressure solutions is available, which can be supplemented by filtering accessories, depending on the needs.


For more insights contact PMD at Plans@propertymd.co.za