* 45 pct of resource zones at water supply shortage risk by 2035
* Climate change not being factored into investment decisions
LONDON, July 13 (Reuters) - Britain has made progress in getting ready for the effects of climate change but certain sectors like water would struggle in the event of severe droughts, said a body which advises the government on climate adaptation.
"We should not think everything is fine and dandy because plenty of water comes out of the taps today. It might not be the same in 20 to 30 years' time," John Krebs, chair of the Adaptation Sub-Committee on Climate Change, told reporters at a media briefing.
The committee's report identified the three largest risks to the UK as coastal flooding, inland flooding and severe weather.
It found that climate risks are still not being factored into long-term decision-making robustly enough in the areas of water infrastructure and land-use planning.
In the water sector, currently 8 percent of resource zones in England are at risk of a supply shortfall in a severe drought. However, this could increase to around 45 percent by 2035 without additional investment, the report said.
The pressure on water supply will only increase in the future due an ageing population. Climate change could up demand by 2-4 percent for household users and by 4-6 percent for industrial and commercial users.
The water companies which could struggle to meet demand in a severe drought are Severn Trent Water, Northumbrian Water and Essex and Suffolk Water, Sutton and East Surrey and Thames Water, the report said.
This does not mean they will run out of water, but they might need to impose restrictions like hosepipe bans more frequently.
Water firms are trying to close the gap between supply and demand by investing 1.4 billion pounds between 2010 and 2015 but climate change has not yet been factored into those investment decisions, the report said.
Reducing average consumption from today's average of 160 litres per person per day to around 115 litres could be cost-effective, it added.
This could be done by upgrading showers, taps and toilets to improve water efficiency and by pushing ahead with the roll-out of water meters which would incentivise consumers to save water.
Nick Reeves, executive director of the Chartered Instiution of Water and Environmental Management, welcomed the report's findings but said it didn't go far enough.
"Much more needs to be done to future-proof our urban settlements," he said.
"This will mean better information and land planning, incentives for the introduction of water efficiency technologies, retro-fitting of homes, universal water metering and urgent adaptation planning by the utility companies, regulators and local authorities," he added.
The committee's report also highlighted measures to reduce overheating in buildings which could be implemented at no additional cost and cost-effective ways of protecting properties against flooding damage.
(Reporting by Nina Chestney)