Hydropower

Title: Map of the Waterways
Type: Map
Date: June 1878
Source: Colonel F.U. Farquhar

Description: Engineer Farquhar prepared this map of the Falls and its waterways in June 1878, after the falls had been reconstructed to be preserved.

Activities:

1. If the lightest color of blue represents the highest water level, how many times does the water level drop by the time it flows past the falls?
   
   
   
   
   Answer: It drops once by the upper dams (by the word RIVER), then a second time as it flows over the apron (the section shaded purple).
2. What might be the purpose of the first drop the water level takes by the upper dams?
   
   
   
   
   Answer: The first drop in level helps move the flow of the river in three directions: toward the Mill Pond, toward the covered canal, and over the Falls itself.
3. What do you think the dark rectangles along the covered canal are supposed to represent on the map?
   
   
   
   
   Answer: The black regions represent various mills or mill buildings that existed along the edge of the Minneapolis Water-power company canal.
4. If the lightest blue shows the highest water and the darkest shows the lowest, how might the high water in the covered canal (at the bottom) reach the lower water?
   
   
   
   
   Answer: The water along the edge of the man-made canal actually flowed through the mills, dropping from the upper level of the river tothe level below. The pressure of the falling water turned the turbines that powered the mills.