Capitol Hill employees have been advised not to use water from bathroom and kitchen faucets for drinking or cooking after tests last month discovered excessive levels of lead in water at the Library of Congress.
The architect of the Capitol issued the warning in an e-mail to employees last week, spokeswoman Eva Malecki said. She described the action as a precaution until results of more comprehensive sampling by the Public Health Service are analyzed over the coming weeks.
"If an isolated fountain or sink test is high, we'll take it out of service and do the necessary procedures," Malecki said.
Employees are free to continue using water fountains across the campus, although some fountains have been turned off, she added.
The architect of the Capitol also monitors the House and Senate office buildings, the Capitol, the Supreme Court and the Botanical Gardens. The e-mail warning about restroom faucets was first reported by Roll Call on its Web site Monday.
The action comes nearly a year after the disclosure that thousands of District homes had water with excessive levels of lead resulted in a massive expansion of water testing by the D.C. Water and Sewer Authority.
The architect of the Capitol has been conducting random water tests since last spring but did not find any significant lead contamination until last month, Malecki said.
She did not disclose how high the lead levels were in the contaminated water found at the Library of Congress or how many faucets were found with high levels. Bottled water has been provided for employees at that building, she said.
Water can be contaminated by running through lead service lines, internal plumbing fixtures or lead faucets, which can leech the toxic metal. Last summer, officials at the Washington Aqueduct added a chemical, orthophosphate, to the water supply in hopes of softening the water's corrosiveness and stemming the leeching. But the process has not been successful, officials said last month.
Although the U.S. Environmental Protection Agency oversees WASA's drinking water testing program, the agency does not monitor the testing on Capitol Hill -- even though those buildings use water produced by the Washington Aqueduct and distributed by WASA's pipe system.
Malecki said that the architect of the Capitol has consulted informally with the EPA's regional office in Philadelphia. EPA spokesman Roy Seneca said that the agency "has a protocol for sampling large buildings, and they agreed to follow it."
Under the protocol, any faucet that produces water with lead levels greater than 20 parts per billion will be removed from service.
WASA spokeswoman Karen DeWitt said the architect of the Capitol has not consulted the agency about the matter and suggested the problem lies within the faucets or pipes in the Capitol buildings.
"It's probably in their infrastructure," DeWitt said.