So, some bad experiences with water lately, hmmm?
Water is used in construction to cure concrete (i.e., to make sure it sets well), but with yesteday's weather, you'd think they wouldn't need it. Concrete guys really like humid days and grumble at dry weather.
Water is also used as a lubricant/coolant when you're drilling stone, which they also could have been doing.
For any other theories, you'll have to ask the 'polite' engineers.