water efficiency - cesa imbizo 2019_kabel… · water efficiency: enhancing water consumption and...
TRANSCRIPT
Water efficiency:
Enhancing water consumption and rainwater harvesting
Author: Kabelo Chabalala
Mechanical Engineer
National Department of Public Works and Infrastructure
Date: 13 August 2019
ABSTRACT
• Increasing scarcity of fresh water
• Population increase, Lack of rain water
• Imposing water restrictions
• The use of grey water
• What is water efficiency?
• Reduction of water wastage
OVERVIEW
• Problem statement
• Related work done by others
• Methods
• NDPW&I contribution towards water savings
• Summary
• Discussion (Q&A)
PROBLEM STATEMENT
RELATED WORK
• Western cape –Water restrictions
WHY CAN’T WE USE SEA WATER?
• Lack of facilities
• Requires a lot of energy through desalination process to
break bonds in salt water
• Thermal distillation – Boiling water vapour
• Membrane separation – Reverse osmosis
METHODS
• Grey water – Used for non-potable purposes
• Rain water harvesting
• Material selection
• Water metering
GREY WATER
SHOWERS, WHB, SINKS, ETC
IRRIGATIONTOILET
WATER TREATMENT
WATER STORAGE
TANK
MUNICIPAL WATER
DRAIN/ IRRIGATION
BOOSTER PUMP
WASTE WATER RECYCLING
RAIN WATER HARVESTING
BOOSTER PUMP
RAINFALL
MUNICIPAL WATER
GUTTER/COLLECTOR
COARSE FILTER
WATER STORAGE TANK OVERFLOW CHANNELLED
TO GARDEN/ SEWER
ROOF
WATER SUPPLY FILTRATION
PIPE MATERIAL SELECTION
37% water lost due to aged and leaking infrastructure
WATER PIPE LIFESPAN
WATER METERING
• Historical water use against population size
• Identify trends and extrapolate future water demands
• Data capturing
NDPW&I CONTRIBUTION
• Custodian of government buildings
• High water demand in public buildings
• NDPWI instrumental and significant in contributing towards
water savings
• Development of green building norms and standards
SUMMARY/TAKE-HOME POINTS
• Reduce water bills
• Reduce water demand
• Pipe material selection
• Water consumption monitoring
