CANAL DENSITY CURRENTS

Three tests were conducted to provide basic data showing the effects of density currents for each of the three conditions in a sea-level canal connecting two seas and intercepting a channel carrying freshwater. Two cross-sectional areas of the canal were tested, 60,000 sq ft, and 300,000 sq ft with tidal ranges in one sea of 10.7 and 22 ft tested for the 60,000 sq ft channel and 10.7 ft tidal range for the 300,000 sq ft channel. The second basin in each test was held at a constant water-surface level throughout each test. The total length of the canal for each test was 260,000 ft. Hydrographs with an excess of 60,000 cfs peak discharge were assumed for each test. Results of the tests indicate that significant density currents can be expected in the 60,000 sq ft channel, whereas density current effects in the 300,000 sq ft channel were confined to a relatively few tidal cycles and were of much less significance than the currents experienced with the 60,000 sq ft channel. (Author)