Blue Marsh Lake - In all the time I've lived within about ten miles of this lake, a few weeks ago was the first time I paid the $3 to get access to the developed areas at the lower end of the lake. A profusion of watercraft were in evidence from one-person PWCs to pontoon boats for floating parties. The impoundment on the Tulpehocken Creek upstream from Reading is a flood control project of the US Army Corps of Engineers.