An infrastructure repair project on Harbor Drive near San Diego International Airport may cause some delays at times for those going to and from the airport through the end of November, according to airport officials.  City construction crews will be in the area of the intersection of Hawthorn Street and North Harbor Drive for the next six weeks to replace a water main and feeder lines, officials said.  As the project progresses, lane closures and cone patterns will change, depending on where the work is being conducted.  The primary impact of the project will be on those leaving the airport toward downtown.  However, generalized slowing in the area may affect traffic in both directions, said airport officials. During the construction period, the Airport Authority advises those going to and from the airport to allow more time for their journey and to consider alternate routes during times of peak congestion.  Alternate routes include using Laurel Street instead of Hawthorn and Grape Streets or using Rosecrans Street and Nimitz Boulevard in Point Loma to reach and depart the airport.