Something in the water?

YNet:

Jerusalem residents are set to drink kosher-for-Pesach tap water during the upcoming holiday.
Jerusalem Mayor Uri Lupolianski asked the Gihon water company, Jerusalem's main supplier of water, to make sure the only chametz-free drilled water will run through
Jerusalem pipes during the holiday.
This is the first year Jerusalem residents are able to drink Pesach-kosher water, as part of Lupolianski's policy to enforce the chametz-law throughout the city.
"As part of the company's public service policy, the company will adhere to the mayor's request, Gihon will bring kosher-for-Pesach water to Jerusalem," said Gihon director Moshe Kalchen.
"The mayor called to thank us for our cooperation and quick compliance with his request," he added.

What this article doesn't explain is what wasn't kosher-for-Pessach about the water which usually flows from Jerusalem's taps, and which the most religious of Jerusalem's residents have been perfectly content to drink over Pessach until now. The answer, of course, is nothing. And how is this water more 'Kosher for Pessach' than any other water?
Shame on the water company for cooperating with Lupoliansky's public relations stunt.