The past week has seen news stories about our unusually dry winter and that unless we have a very wet spring there could be a drought, especially in the southeast of England.

The Defra Water Summit  chaired by Caroline Spelman - Secretary of State for DEFRA took place Monday 20th February and on the same day Sainsbury's held a Corporate Responsibility dinner which focused on the water used by our suppliers and customers.

In Sainsbury's we treat water seriously and our 20 by 20 Sustainability Plan targets focus on robust water stewardship, ensuring that our supply chain approach is sustainable in areas of water vulnerability.

My team is responsible for how we use water in our own stores and I thought it would be worth sharing with you what we have been doing over the last year or so to make significant headway in using this valuable resource wisely and how we are reducing our water consumption.

In Sainsbury's stores, the greatest use of water is through flushing toilets and washing hands, followed closely by consumption in both our customer cafes and colleague restaurants and then through our fresh food counters and bakeries. Water is also used for cleaning and watering plants in the landscaping around the store. Larger stores with petrol stations often have car washes and although these use significant amounts of water, the good news is that it's recycled.

Whenever we set about challenging ourselves to make a reduction, we always start by making sure we are clear on how much we use in the first place. This is important, as to make a saving you have to start by truly measuring what you use; this is where we have focused our efforts, by installing automatic meters and closely examining billed usage on a store by store basis. 

As of today, we have over 200 stores with automatic meters and we will be increasing that to 350 in the year ahead with an aspiration to have all our supermarkets with automatic meters by 2015. Checking our water billing against automatic metering raised significant numbers of queries and led to quite a number of leaks being identified and stopped quickly. We have established that the cost of fitting meters has been offset by the savings we have made from eliminating leaks. We also partner with a specialist company whose key accountability is to monitor our stores' water bills and automatic metering. We are gaining a much better insight into how much water our stores use throughout the year, so if a leak occurs it gets highlighted by our partner and dealt with quickly.

We are really keen to trial innovative technologies in our quest to beBritain's Greenest Grocer and this very much includes saving water. Where we prove that a new innovation truly saves water we try to incorporate them into our standard specifications and where possible roll them back into our existing stores too.

A great example of this is the taps that we use for washing hands in our colleague and customer areas. We have looked at so many different types with the aim of finding ones that are not only really easy to use but turn themselves off after just a few seconds in case our colleagues and our customers forget. The model we use fits both of these requirements and has made a big difference to our water consumption.

We also install toilets that only flush 4.5 litres of the 6 litres in a cistern and we use a unique valve system that allows us to install hygienic urinals that literally use no water at all. 

In a few weeks time we will be coming to the end of our annual 'Water Reset Programme' on 140 of our stores. This is where we make sure that everything is operating as it should and we introduce new technologies and equipment to improve our water consumption. The great news is that just on this current year's programme we've made savings of around 320,000 cubic meters - which is the equivalent to the amount used to fill128 Olympic size swimming pools. I am also delighted to share that new Sainsbury's  supermarkets that opened this year use 50% less water than our stores were using 6 years ago in our baseline year 2005/06.

Another key opportunity in our quest to use less mains water is for us to be truly sustainable by doing our best to capture and use, where we can, the natural resource of rain water. Since 2008 we have been installing rainwater harvesting systems in our new stores and on new automatic car washes. Currently the rain water is only used to flush our toilets but we are exploring opportunities to use this water for watering the plants in our landscaping. We are also working hard to establish how we can install rain water harvesting into our existing stores without disrupting car parking and inconveniencing our customers in the process - so watch this space!

Our colleagues are truly our "eyes and ears" on the ground and they are really important in spotting problems and calling our engineers out so they can fix dripping taps and leaks. 

Having accountability for operational water has meant that my focus on avoiding leaks has been heightened - so much so, that I have become a bit of a 'Leak Spotter' at work and at home!

I have contacted my local water company twice to alert them to two different major leaks in the road leading to my village. You might want to think about saving water in your own business or home and become a 'Leak Spotter' too.

And at this time of year, after very cold weather spells, the likelihood of leaks increases so if do see visible leaks in the roads on your journeys, making that call to your local water company to report them will really make a difference as 'every drop counts'.