Cold water supply and Treatment Barry Spick

Objectives State the regulations and the purpose of the regulations covering cold-water Describe how water is collected, stored and distributed. Describe the cold water service from mains to a dwelling (including water meters) Barry Spick

Standards and Regulations What is the main British standard detailing installation of Hot and Cold supplies? BS 6700 Others BS 8000-15: Workmanship for Hot and Cold supplies Water Regulations Barry Spick

In chemical terms water is a compound of two gases : Hydrogen and Oxygen H20 Water has solvent power according to the strata or ground it passes through. Soft water, easy to produce a lather, doesn’t contains salts such as calcium carbonates or sulphates Hard water difficult to obtain a lather, does contain salts such as calcium carbonates and sulphates Barry Spick

How is hardness classified? Water is classified by the number of parts of calcium per million parts of water Soft water 0 to 50 Moderately soft 50 to 100 Slightly hard 100 to 150 Moderately hard 150 to 200 Hard 200 to 300 Very hard over 300 Barry Spick

Permanent or Temporary Hard? Temporary hardness leaves lime scale deposits on the inside of pipes and plumbing systems. Permanent hard occurs when water dissolves sulphates of limestone. Barry Spick

The water cycle Barry Spick

Wells There are three types of wells What type of well is this? A shallow well Does not penetrate the impervious strata What class is the water Water is classified as dangerous Pervious Impervious Pervious Shallow well Barry Spick

Wells What type of well is this? Deep well Penetrates the impervious strata What is water classed as Water is classed as wholesome Pervious Impervious Pervious Deep well Barry Spick

Artesian Well Water Penetrates under Impervious layer Water Table Pervious strata An Artesian well is below the water table and the ‘head’ of water causes the water to eject under pressure Impervious strata pervious strata Barry Spick

Summary of water source classification Wholesome: Spring water Deep Well water Upland surface water Suspicious: Stored rainwater 5 Surface water from cultivated land Dangerous: River water Shallow well Barry Spick

Is your water fit to drink? Yes it is, but only after it has been through these processes: Strained Filtered Chemically treated Sterilised Barry Spick

Water Distribution Reservoir Water Treatment Local Mains Trunk Mains SUPPLY Reservoir Water Treatment Local Mains Trunk Mains Principle Mains Barry Spick

End of Part One Barry Spick

Cold water supply and Treatment 2 Barry Spick

Connections to water mains Connection to main made with a ferrule whilst the main is still live via a “Wet Box” Connections can only be made by the Water Undertaker, in this area Yorkshire Water Barry Spick

How is the water service pipe connected to the water main? Water mains are made from various materials Steel PVC Cast – iron PVC: is now used extensively on new installations and mains replacements Barry Spick

Connection from main into building Pipe or duct Sealed at both Ends to prevent vermin etc 750mm To 1350mm Boundary Gooseneck Ferrule main Supply pipe Communication pipe Service pipe Barry Spick

Key points about service pipes Pipes to laid between 750mm minimum 1350mm maximum More than this would prevent ease of access Metal pipes should be protected against corrosion especially in acidic soils. Use of plastic coated pipe Wrapping pipe in anti corrosive tape Install pipe in duct Minimum size of service pipe is 15mm Barry Spick

Key points about service pipes If service pipes are laid on a ‘brownfield site’ (contaminated land) Be manufactured from metallic material or plastics barrier pipe Why? To prevent contaminants from the soil permeating through the plastics material into the water supply. Preferred location of isolation to whole of property Above ground – immediately on entry to the building Barry Spick

Key points about service pipes Stop valve to BS 1010 Drain valve : Screwdown type conforming to BS 2879. Pipe to be within duct at point of entry to dwelling If pipe is installed less than 750mm from external wall then: Insulated to a depth of 750mm Barry Spick

Stop valve chambers Ease of access to stop valve Minimum diameter of pipe: 150mm plastic pipe or earthenware Sited on a firm base Top to have stop valve cover Usually made from metal Barry Spick

External water meters Now becoming more widespread on domestic properties Meter pipes can be obtained pre-plumbed Are adjustable Top of meter to be no more than 300mm from lid Barry Spick

Internal Water Meters Water meters must have fittings to allow connection/disconnection without the use of heat Must be able to be isolated Have a permanent cross bond Max 1.5m from floor level Barry Spick

Internal Water Meters Cont’d When a meter is fitted in an enclosure Front of meter to be no more than 300mm from the front of enclosure Enables reading of meter Rules regarding connection as before Permanent cross bond to be fitted. Barry Spick

End of lesson Barry Spick