Thames Water responded in writing to some of the main criticisms made by the people who emailed Panorama. This is what they said.
THAMES WATER: Thames Water has spoken extensively about the issues raised by Panorama in previous interviews with the BBC. These responses are already in the public domain.
PANORAMA: Why have you not met your leakage targets since 1999/2000?
THAMES WATER: Reducing leakage is our top priority, so missing leakage targets has been immensely frustrating. We made enormous efforts in this area, including a massive programme of investment and increasing staff by 44%.
Our London network contains 10,000 miles of pipes and of these almost one third are more than 150 years old.
Our work to find and fix leaks in this network, which is much the oldest in the country, is essential and we are currently repairing 240 leaks each day - one every six minutes.
The only way to achieve sustainable reductions is by replacing whole areas of the oldest and leakiest pipes. We are doing this as rapidly as possible with major projects in more than 30 areas of London but it is a long-term commitment.
PANORAMA: Who gets a better deal - your customers or your shareholders?
THAMES WATER: Our customers are always our greatest priority. They enjoy unrivalled drinking water quality and although we very much regret the need to impose a hosepipe ban the current restrictions are the first for 15 years.
We need investors to continue to fund the massive programme of replacing London's Victorian mains and other essential work. Shareholders would not invest without being offered a return on their investment.
In the last five years, for every pound we have paid in dividends to shareholders we have spent four pounds on improving our water and wastewater networks.
PANORAMA: Do you really believe that your leakage levels are not worsening the drought situation?
Leakage levels in London are unacceptably high, but they are at the lowest levels for four years and we have accelerated our programme of Victorian mains replacement to make further improvements as rapidly as possible.
Leakage affects the amount of water available for supply from the time when reservoir levels start to drop in the summer until the reservoirs are full again in the autumn. This is a period of about 100 days.
Over this period, the amount by which we missed our leakage target (34Ml/d) represents about one and a half days supply for London.
At other times of the year leakage is, of course, a waste because we are taking and treating more water from the environment than would otherwise be necessary. But it does not affect our ability to supply our customers.
The drought is the result of an extended period of below average rainfall over a period of 20 months, which has affected the whole of the South East and not only the Thames Water region.
Other water companies in the South East area, who do not have the same leakage issues that we do, needed to impose restrictions at an earlier stage than we did.