A MIRFIELD inventor has won a £40,000 grant for a water-saving device he created.

David Wilks, a former supply teacher, received the cash and a major award for his device which could save an estimated 675bn litres of water every year.

Interflush is a small device that fits to standard siphon toilets and allows the user to alter the amount of water used during flushing.

The product has earned Mr Wilks the Shell Springboard Award, which is presented to small businesses with innovative and energy-saving ideas.

The award attracted more than 250 entries from all over the UK, of which 25 were shortlisted.

Mr Wilks, of Calder Road, received his award from Shell UK chairman James Smith.

Mr Wilks said: "It is becoming increasingly essential that we all save water. The UK's changing climate conditions will force us to cut back on daily water usage and wastage.

"Interflush is a simple device with the power to radically reduce our water consumption."

He added: "Working on this product has been a labour of love and it's tremendous to get such high profile acknowledgement of its potential environmental impact.

"I am going to use the money to invest further in the manufacturing process and employ additional staff."

The device can save between 25 and 30 litres of water a day for each person - at a time when impending water shortages are a worry in some parts of the UK.

The kit fits on existing siphons and cisterns with front mounted handles.

Interflush allows interruptible flushing. Users hold down the handle until the pan is clear. Upon releasing it, the flushing stops, eliminating any water wastage.The device could save as much as 47% of water used in a single flush.

Mr Wilks, 53, who used to teach science, maths and technology at schools across West Yorkshire, is selling about 500 of the devices a week on the internet.

The device cost £19.90 to buy, but could save householders more than £1,000 over 10 years. He went into production himself after being unable to find a manufacturer.

* Toilet flushing is the single largest user of household water, accounting for up to 40% of the total

* Each person uses about 150 litres of water every day - with 60 litres accounted for by toilet flushing

* The average person flushes the toilet six times a day

* Water use in the UK has increased by 70% since 1970

* Almost one in five UK families owe money to their water company - with debts totalling almost £1bn

* Britain is forecast to have its worst drought in 50 years this year