Passionate about Eco Home Building?

Building or Renovation – Water Conservation Tips

Ella Walters from the eco designers writes to assist your ways to change at home.

Intro

NZ homes use, 25 – 30% of water for flushing toilets, 33 – 35% for baths and showers 20 – 25% in the kitchen, and 20 – 25% is used in the laundry. A family of four uses around 500L per day not including water used in the garden (a garden sprinkler can use 900 litres an hour). Per year, the average person uses around 75,000 litres and the average household uses around 200,000 litres.

Contents

• Free Eco Design Advisor Service
• Water Conservation tips
• Rainwater Harvesting
• Grey Water Recycling
• Composting Toilets and Worm Septic Tanks
• Solar Hot Water

Free Eco Design advisor Service

The eco design advisor service provides free and impartial advice for people planning to build or renovate their homes to improve family health and comfort, reduce impact on the environment.

Available to homeowners, designers, builders and trades-people, the service is provided by Sustainable Wanaka and funded and supported by the QLDC, BRANZ MfE and EECA.

Eco Design Advisors Ella and Christina can provide tailored advice on insulation, energy efficiency, water conservation, sustainable building materials and passive solar design. Building or renovating plans can be reviewed at any stage of development.

To make an appointment and take advantage of this great free service contact Ella in Wanaka on Office 03 443 5057, mob 021 031 4258, email ella@seedbuilding.co.nz or Christina on mob 027 583 7444, email Christina@seedbuilding.co.nz

Water conservation tips and rainwater collection

Rainwater Harvesting

Installing a rainwater tank is a great way of reducing your mains water consumption. For every millimeter of rainwater that falls, you will collect approximately 1 liter of water for every square metre of roof area.

Management

Most rainwater management systems provide a hassle-free way of integrating rainwater into your home for use in the laundry and for flushing toilets. By using sensor and smart switches, they can switch automatically between mains and rainwater supply depending on the level of the rainwater tank. Water pressure required by washing machines and irrigation systems is provided by a pump.

Maintenance

Maintenance of the rainwater harvesting system is essential as rainwater is easily contaminated by debris. Ensure that gutters and free from leaves and animal waste so that sludge does not build up in the tank, which could result in clogged filters, pipes and pumps. Filters and diverters are the key mechanism for keeping the tank clean. You will need to ensure that your roof surface is suitable for collecting rainwater to avoid contaminants such as lead entering the system.

Garden irrigation

Today it is more important than ever to use water resources wisely and to irrigate wisely, even with three great lakes on our doorstep! Drip irrigation from a rainwater source provides you with a very efficient method of irrigation as water is applied to the root zone which eliminates over spray and evaporation. Drip irrigation can be in the form of drip line or individual drippers per plant.

Greywater and blackwater recycling

Greywater recycling

Most homes produce around 100-200 litres of greywater per person per day. Greywater recycling systems divert wastewater from the showers, bathroom sink and laundry for use in the garden or can be treated and used in the home. Greywater is mildly polluted with soaps and detergents and can contain levels of nitrogen, phosphorous and potassium. These minerals are generally considered beneficial to plants. Use garden friendly products, soaps and detergents to ensure that the correct mineral levels are maintained.

Most greywater recycling systems come with smart switches, which enable you to switch off and on a greywater source and allows you to divert harmful contaminants from your garden irrigation system.

Tips for managing greywater systems

• Use liquid detergents rather than powders; most powders are very high in sodium and salts, which can injure plants
• Avoid cleaning products with boron, which can be toxic to plants
• Avoid use of chlorine bleach
• Avoid caustic drain cleaners and other chemicals with unknown effect on plants
• Landscape the greywater irrigation field with plants that are tolerant of alkaline (basic) soil; acid-loving plants should be avoided.
• When cloth nappies are being washed in a washing machine, the drain should be disconnected from the greywater system
• If highly contagious illnesses are present, the greywater system should be switched off, and all wastewater should be disposed of using the conventional system
• Greywater should not be used for irrigating vegetable gardens

Black water and water conservation tips

Black water and worm septic tanks

Black water is wastewater from the kitchen sink, toilet and dishwasher and can be treaded onsite. Worm septic tanks require no chemicals to treat the water onsite as opposed to regular septic tanks that use chemicals to breakdown waste.

A composting toilet is a dry or waterless toilet that uses natural processes produce useful compost, after a resting period, which depends on the type of the toilet. Composting is a form of biological decomposition that takes place in a controlled environment, the four key requirements needed to maintain this environment are oxygen, carbon, nitrogen and moisture. Composting toilets are odourless and can reduce indoor water use by 20-30%.

Water conservation tips

• Use a shower timer to cut down on water usage
• Switch off the tap when brushing your teeth
• Have baths instead of showers. Baths use up 100 liters of water each time you have one.
• Fix leaking taps
• Install low flow shower heads and aerators on taps. By installing a low flow shower head you could save up to 20,000 liters of water per person each year.
• Rinse your dishes in a sink of water, not under a running tap, and use your dish washer on the eco cycle and only when full
• Front loading wash machines use less energy and water than top loading machines
• To check if your toilet has a leak, put a little food dye in the cistern. Wail 15 mins (don’t flush) and check the water in the bowl. If the colour appears in the bowl the cistern needs repairing.
• Install a rain garden
• Garden to the climate, reduce areas of green grass that require lots of water
• Opt for more robust types of grass that require less water
• Specify water-efficient appliances. Ask the manufacturer for details on how much water each appliance uses, check the appliances water star rating The difference between a 4-star and a 1-star could be more than 10,000 litres per year. WELS database www.waterrating.gov.au/publications/wels-brochure.html

• Avoid specifying in-sink waste disposal units. These require a lot of water to operate, and they overload sewage treatment plants or in-ground septic systems with organic matter. Design and install customized organic waste disposal receptacles instead.