COMMERCIAL FISHERIES REVIEW 



Vol. 28, No. 9 



STUDY AREA 



Since large ships travel north on the Menomonee River beyond the junction with the Mil- 

 waukee River, the air bubble curtain was installed in the Milwaukee River just north of its 

 confluence with the Menomonee before reaching the heavily populated downtown business area 

 (fig. 1). The east bank of the river was chosen as the site to install the air compressor unit 

 because a municipally owned lot was available at that point immediately adjacent to a fire sta- 

 tion that was manned continually (fig. 2). The availability of fire department personnel to 



Fig. i - City of Milwaukee Harbor Area: (1) Government break- 

 water, (2) Sewage Treatment Plant - Jones Island, (3) Kinnick- 

 innic River, (4) Menomonee River, (5) North Water Street 

 bridge, (6) Buffalo Street bridge (7) Milwaukee River, (8) Fire 

 station, (9) Compressor and other equipment, (10) Air hose. 



Fig. 2 - Diagram of study area: (1) North Water Street bridge, 

 (2) Fire station, (3) Equipment location, (4) Menomonee River, 

 (5) Air hose, (6) Milwaukee River, (7) Buffalo Street bridge, 

 (8) North Water Street. 



check on the operation of unit assured uninterrupted operation. At this point, the hose was 

 500 feet long and transversed the river on a 45° angle to the shoreline. This would tend to 

 lead the fish along the trailing edge to the west bank of the river where commercial netting 

 was planned. The depth of the water in this area was about 22 feet. 



EQUIPMENT AND INSTALLATION 



THE PLASTIC HOSE : Two lengths of plastic hose, rated to withstand 100 pounds 

 square inch, were connected by a regular air hose reducer fitting. The first 250 feet 

 hose was 1 inch in diameter and the remain- 

 ing 2 50 feet was |-inch diameter. Holes 

 (0.0135 -inch diameter) were drilled every 6 

 inches with a No. 80 jewelers drill. One end 

 of the hose was plugged. A length of |-inch 

 chain was attached along the entire length of 

 the hose by nylon seaming twine to keep the 

 hose on the bottom in the desired position. 

 As the hose was drilled and the chain attached, 

 the two sections were placed on two large 

 reels aboard a barge (fig. 3). This technique 

 made it easy to place hose on the bottom of 

 the river by attaching a line in the desired 

 diagonal across the river and moving the 

 barge along this line (fig. 4). The end of the 

 plastic pipe was secured to a rigid pipe se- 

 cured to a piling on the west bank of the riv- 

 er (see cover page). Fig. 3 - Barge used to place air hose. 



per 

 of this 



