Motorists using Derstine Road in Towamencin and Hatfield Townships should expect construction delays and detours next month. Workers will install water and sewer lines under the road starting Monday, September 13, between Funks Road and Kimberly Way.  They will serve four buildings under construction at Derstine Run, a housing complex that Advanced Living Communities is building.  It will have 240 affordable apartments for seniors on a 24-acre site.  The water and sewer line work will take about four weeks.  During that period only local traffic, emergency vehicles and school buses will be allowed on that stretch of road between 7:00am and 3:00pm weekdays.  It will be open to all traffic outside of those hours.