The average Irish adult uses about 150 litres of water per day at home.
150 litres per person equals about 600 litres for a household of four persons, or about 220,000 litres each year. Ok, that’s average! What can we do? As architects we can ensure that new developments or renovations use taps and toilets that use less, that we harvest any water that we can for re-use in gardening or external washing and for the flushing of toilets. If the average efficient toilet flush uses 8 litres, and we each flush the toilet about 5 times a day, that’s 40 litres if the toilet is modern and efficient. For four people that’s nearly 60,000 litres each year. All the other uses, washing ourselves, clothes and dishes, washing the car, the patio, the windows and the dog use water too! If we washed the patio, the car, watered the garden and flushed the toilet with recycled or harvested water we could significantly reduce our net water consumption. Dishwashers use about half the water that is used by washing dishes by hand. Where renewable energy from sustainable sources is used, then using a dishwasher is more environmentally viable. In essence we could easily half our consumption with little change to our life style. Add to this the question, is our life style sustainable? Perhaps we should examine our life styles in order to ascertain whether savings could be made with small alterations.
Water charges are proposed in Ireland and are roughly based on the average adult use. The proposed domestic allowance is slightly in excess of this. It is not clear as yet whether the allowance will be the amount of water that is proposed to be used within the standing charge. As the standing charge is however cited as being for the provision of water metering services and maintenance of the system it appears that the standing charge may not include any amount of water. This is reflected in the low annual standing charge of €240. It has been reported that the annual real costs could average €560 per household. Whether this cost is passed on to customers directly or through other ‘taxes’ has no bearing on it being a real cost. Removing the standing charge results in a cost per litre of 0.15 of one cent.
If we reduce our consumption by half at home we can theoretically reduce the cost by about one third, or €165 per annum. Do we need more incentive? Yes! Using more water away from home is definitely going to cost us more, added to which any unnatural increase in water use away from home is likely to yield an increase in general services costs. The gym will get more expensive.
However, the imagined incentive is to use less water rather than alter our lives to be more efficient. This may well lead to some of us neglecting the more important things in life, like drinking water and being clean. The real rewards should perhaps be applied to those who implement measures to save water such as using low capacity toilet cisterns, low use taps, rain water and waste water harvesting. A possible incentive is to have a low standing charge that includes the use of an efficient water use relative to the size of house. This would make it possible for people to live with the standing charge. In large cities the treatment of waste water for human use is common with their often being no other option. The concern is not the final quality, treatment in the developed world for this waste water is excellent. The concern is the cost and the need to improve the capacity to produce high quality water. Overtaxing these systems with surface water or wasted fresh water incurs greater cost. Efficient separation of drainage systems needs then to be established everywhere and enforced. There is little effect in proposing that all new development have separate drainage systems without implementing these systems in the public areas. There remain large areas predominantly of high density where separate systems do not exist other than in private developments. This separation is then cancelled once in the public domain thereby taxing the treatment systems unnecessarily.
Why save water? In Ireland in rains, there is plenty of water! The truth is that this water is not treated and not fit for human consumption. Of more concern is the depletion of the aquifers in Ireland. Despite the apparent increase in rainfall, the aquifers in Ireland and throughout Europe and the developed world are in danger of continuing to deplete. The very essence of our land is drying out, withering below us. This is invisible and difficulty to imagine when floods increase. The consequences of our continuing disregard includes in the short term ever rising services costs, but in the long term may be far more serious. These aquifers are our source of naturally treated water, filtered through ground systems over many years. The water cycle relies on natural surface water permeating back to the aquifers below. Prior to treatment, waste water has high levels of various toxins, chemicals from washing, detergents, oils and so on. These may well contaminate future aquifers. This is an important reason why foul drains should never mix with surface water drains. Add this contamination to low levels in aquifers and the proportionate contamination is higher.
In the developed world we can easily reduce our water use by as much as 75%, this would based on the current proposal in Ireland yield a saving in financial terms only of approximately 44%. A lot of effort for apparently little return! The world despite the impression that we are given is only in small part financial. It would be fair to reflect the truth and afford a consequential and equitable reward in terms of finance to those practicing restraint. Were the cost of this restraint alone credited to those diligent more will be achieved. Revenue is needed to repair and upgrade the public systems. Increasing the capacity of the treatment systems to cater to the actual demand (including surface water) without trying to reduce that demand does incur additional costs. The solution requires the cooperation of the people and the authorities in their combined attempts to address the problem. We should cooperate both with use constraints and effluent control. Our future is important!