Proceedings of Sixth Annual Meeting 



59 



The amount of work to be done, the exceedingly Umited time 

 in which to do it, coupled with the greatest shortage of labor in the 

 history of the country, made it impractical to attempt to place the 

 entire area under control in one season. The original plans were, 

 therefore, modified to include only that territory immediately adja- 

 cent to the League Island Navy Yard, the Hog Island shipyard, the 

 Westinghouse Electric and Manufacturing Company, and the lesser 

 plants and war operations lying between these all-important in- 

 dustries. 



This smaller area includes all of the South Philadelphia section 

 and the territory west of the Schulykill, between the Delaware 

 River on the south and Darby Creek on the west and north. It 

 contains, in round numbers, twenty square miles of territory, of 

 which approximately eight thousand acres is diked marsh land lying 

 from one to three feet below mean high tide. With the exception 

 of the area served by a single pumping station operated by the city 

 of Philadelphia, the entire territory was drained by means of auto- 

 matic tide-gates, supplemented, in some cases, by hand operation on 

 the diurnal tides. Owing to tidal conditions in this region, these 

 gates, even when hand-operated, do not average more than one 

 hour's play on each low tide. There is also a certain amount 

 of leakage, which in the case of gates not recently repaired, totaled 

 millions of gallons a day. The territory is traversed by more than 

 a hundred miles of old creeks, watercourses and ditches, the ma- 

 jority of which were badly choked with the accumulations of years. 

 During the summer season they were in addition filled with a dense 

 growth of cattails, wild-rice and spatterdock. Large portions of the 

 marsh areas were covered with a similar growth. Drainage under 

 these conditions was far from effective and the water lay virtually 

 stagnant in marsh, creek and ditch throughout the area. 



The co-operative plans contemplated the restoration of the exist- 

 ing drainage facilities to full efficiency by repairing the dikes and 

 tide-gates and by cleaning all watercourses and ditches necessary 

 to a proper runoff of the surface water. They also contemplated 

 the installation of additional pumping stations, together with the 

 extension of the system of drainage channels and ditches, so that 

 the entire area could be unwatered even during abnormal weather 

 conditions before sufficient time elapsed for the emergence of adult 

 mosquitoes. 



