The project, expected to run through Dec. 7, will allow Connecticut Light & Power crews to install power transmission lines connecting to a new substation on Fitch Street.
While the station's westbound lot is closed, alternative parking for commuters will be available at the eastbound parking lot, 232 East Ave.
When completed, the project should produce improved electric reliability and additional parking spaces at the westbound lot, officials said.
The work will not affect regular train service in East Norwalk.
Signs, flagmen, police officers and parking personnel are scheduled to be on site to direct rail passengers to the platforms during commuting hours.
For more information, contact the Parking Authority at 203-831-9063.