Drinking Water 6 March 2013 Andy Case CEnv C.WEM BSc (Hons) MCIWEM

About me Run Case Environmental, Teignmouth based environmental consultancy established in Worked in the water and environmental industry for over 10 years, including South West Water and the National Trust Work across Devon & Cornwall and further afield looking at mainly private water supplies and related issues.

Water – The Facts 70% of the surface of the Earth is water 98 % sea water 1.5 % ice 0.4 % found in aquifers, rivers & lakes 0.1 % atmosphere, plants & animals

Clean Water 800 million don’t have access to clean water 3.5 million die of drinking water related illness each year 700,000 of these are children – approximately 2000 per day In developing countries half of all hospital beds are filled with people suffering from poor quality water & sanitation.

Sources Rivers Reservoirs Groundwater (springs, wells and boreholes) What about sea water?

Sources - Groundwater Spring Borehole Well

Source to tap? ££££ Reservoir Town Meter

Typical Mains Water Treatment for Surface Sources Inlet Flash mixer Clarifier Sand filter Carbon filter Chlorine contact tank Coagulant added pH corrected Chlorine added Phosphoric acid added pH corrected To final water tank and distribution

Source Water Quality Heavy rain - spate conditions Run-off from fields – animal waste, fertilisers, pesticides Operation of combined sewer overflows Diffuse pollution – pesticide degradates, nitrate Industrial pollution Fuel/chemical spills Algal blooms Saline intrusion

Source Water Quantity Needed most when less is available Areas with the least rain have the biggest demand for water Most rain falls in winter Minimum abstraction levels Recharge rates for aquifers

Water Supply in the South West Big population variation, in summer some areas can double Seasonal rain fall expectations Topography 33% of the countries coastline 2.5% of the population Over 30 water treatment works 600 sewage treatment plants

Drinking Water & Climate Change Many issues already surrounding production and distribution of drinking water Very power & chemical intensive to operate & supply – if oil/gas supplies stopped we’d have no water Importance of sustainable water management; - SUDs, allowing aquifers to recharge, limit run-off - Land management (chemicals, crops, livestock etc) - Water security.

Water Use Water use has increased from 90 litres per person to 180 litres per person in 50 years – why? People want to be cleaner Appliances such as dish washers & washing machines Gardening Increased car ownership

Domestic Water Use

Water Saving Measures Showering – reduce time, fit aerator to showerhead Use washing machines/dishwashers only when full Invest in efficient goods Bowl in sink (washing, food preparation) Modern toilet/water saving device Check for leaks – not just taps but toilet overflows Garden – grow plants that require little water, protect from wind & sun Outside – avoid using the hosepipe

Alternative Water Sources – Rain? Roof collection Average roof size of 80m 2 Average rain fall in South West UK 800mm per m 2 Annual amount 64 m 3 Other points of collection? Patios/drives Outbuildings

Rain Water Benefits Naturally clean Reduce run-off/flooding, contribute to sustainable urban drainage Potential saving £150/year Reduce demand on mains Problems Acidic – pH correction or plastic plumbing needed Maintenance Can collect debris/detritus from roof – first flush needed Position of tank to be useful Storage & potential bacterial concerns Technically need to inform SWW so they can charge you sewerage

Alternative Water – Grey Water Either partially treated water or previously used water Limited uses due to quality Require modification of existing plumbing Treatment required, cost implication, servicing Potentially harmful to plants and environment depending on previous use Microbiological issues with use – legionella etc.

Way forward? Encourage rainwater harvesting in new builds? Sustainable Urban Drainage? Variable rate billing? Wash less?

Questions?