Starting Monday, traffic on Jefferson Street between Kennedy Boulevard and Cass Street will be open one-way northbound only during the installation of a new water main, a project expected to take nearly four months.
 
  During the construction period metered parking will be limited, and delays northbound should be expected, although at least one northbound lane will be kept open at all times.
 
  Alternate northbound routes include Florida and Nebraska avenues. Pierce Street is an alternate southbound route.