Streamflow trends over the past year at Valley Creek At Pa Turnpike Br Near Valley Forge in an interactive calendar format. View seasonal patterns on the river and see how an evolving climate has affecting streamflow levels over the past year. Click on any day to see what the streamflow was for that day, or sign up for a free account to view data for the past 110,834 days. The streamflow average over the past 10 days was 12.78 ^cfs, with a day to day variation of about 4.8^cfs.