Blue water occurs when chemicals in the water react with the copper in copper pipes, causing it to either dissolve into the water (clear blue) or else corrode from the pipes without dissolving (cloudy blue). It happens worldwide and with both rainwater and mains water.
One of the easiest ways to deal with it is to let the tap run until water that has been sitting in your copper pipes has flushed out and there is fresher water coming through. Another method is to change the copper pipes to plastic, though you may notice a plastic taste to the water. The third alternative is to drink bottled water, which tastes better and may be safer than copper water.
If your water is cloudy blue you're in luck because you can get filters to catch the copper particles. The copper dissolving causes clear blue water, so the more expensive filtration process needed may not be cost effective. If you are concerned about the amount of blue staining on fixtures, you may ask your water authority to test for copper levels. Although it will cost you, at least you'll find out if the levels pose a health risk.
If you use tank water, there are a few things you can do to help stop the corrosion. Adding chlorine seems to reduce copper corrosion, so calculate the amount of water in your tank and add hypochlorite at the rate of 0.5mg/L. Bottled water however is a better option for drinking/cooking purposes as it is usually filtered and is chemical-free.
Need information on bottled water as an alternative to copper water? Get bottled spring water delivered to your home or office with Tranquil Water (http://www.tranquilwater.com.au) for clean, great-tasting water. Water cooler dispenser available for lease.