Water Systems Particularly Vulnerable to Hacking, Senators Told

Employees at the Boston Water & Sewer Commission knew they were under cyberattack last year when every printer in the office started spewing out ransom demands.

The attack complicated day-to-day business and the recovery was expensive, but John Sullivan, the commission’s chief engineer, suggested it could have been far worse. He said precautions were in place to prevent any impact to public health or the environment.

In testimony Wednesday before the Senate Environment and Public Works Committee, Sullivan and others said such attacks show how vulnerable critical infrastructure in the U.S. is to hackers. Recent attacks on a major fuel ...