226 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



enacted in 1851, yet in 1863 the State formally acknowledged the dam 

 as satisfactory. The hostile sentiment among the up-river residents 

 increased, culminating in a mass convention at Harrisburg, composed 

 of four or five hundred delegates, which resulted in the passage of an 

 act by the legislature then in session requiring that the several com- 

 panies owning or interested in dams on the Susquehanna should erect, 

 within six months thereafter, such sluices or other devices as would 

 permit the free passage of shad and other fish up that stream. 



In compliance with this enactment the canal company owning the 

 dam at Columbia, selecting a point about a quarter of a mile from the 

 western bank, where shad were accustomed to gather in the greatest 

 number during the season, removed a 40-foot section of the dam and in 

 that space built a new subdam, the top of which was about level with 

 the water below. The lower slope of the subdam was placed at an 

 inclination of 1 in 15, and the sides of the aperture in the main dam 

 were dentated, so as to promote the formation of eddies in the current 

 passing over the subdam. This structure did not appear to answer 

 its purposes, and in 1873 the State made an appropriation for another 

 fishway at that point, the designs consisting of a single trough 120 

 feet long by 00 feet wide, running through the dam, and about 150 feet 

 back into the part below, with its upper end sunk 2 feet below the 

 crest of the dam, the sides of the trough or fishway being protected by 

 strong abutments built up on both sides. This also proved ineffectual, 

 and in 1880 a third fishway was placed in the dam, consisting simply 

 of an opening 125 feet wide, this plan being chosen because it conformed 

 to a break in the dam, experience having shown that shad passed 

 through such an opening more readily than through any fishway that 

 had been constructed. In 1886 a fourth fishway was constructed on 

 the site of the one built by the canal company in 1866. 



While shad do pass above the dam, yet during recent years few 

 have been caught above Columbia, except when breaks exist in the 

 obstruction. This was the case in 1873, 1877, 1895, 1896, and possibly 

 during some intervening seasons. The break in 1895 occurred in the 

 spring and many shad ascended as far as Clark Ferry. The men along 

 the river were not prepared for their coming and few fish were caught. 

 The break was not repaired, and in 1896 some few seines were used 

 which did fairly well in those places where the bottom was sufficiently 

 clean for hauling. The principal places above Columbia dam where 

 shad were caught are Bainbridge, Marsh Bun, Newmarket, McCormack 

 Island, and Duncannon on Susquehanna Biver, and Newport on the 

 Juniata. Seines were the only apparatus employed, and the number 

 of these between Columbia dam and Clark Ferry dam was 14, with 2 

 on the Juniata near Newport. The length ranged from 250 yards down 

 to 80, with 4^ to 5£ inch mesh. The catch in the 14 seines on the Sus- 

 quehanna numbered 2,417 roe shad and 3,276 bucks, valued locally 

 at $1,696. The 2 seines at Newport, on the Juniata, caught 280 roe 

 and 420 buck shad, worth $287, making a total of 6,393 shad taken 



