C.E.,
District Engineer.
OF THE COMMISSIONERS OF PUBLIC WORKS.
213 of some dams and unimportant shoals, and the construction of a swivel bridge in connexion Appendix (E.)
with the present wooden bridge of Agivey.
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The tidal lock has since my last report been entirely completed, including the Annual Report of excavation of its tributary, affording 8 feet depth of water on its lower sill at half-tide Jfr.
C^k?;i?^tle3r
level.
The gates have been made and hung, and the sluices and machinery connected with them erected on the most approved principles.
The western weir, 350 feet in length, has, with considerable difficulty, but entire success, been closed and coped, and been in operation since the month of June.
The wharf wall, 540 feet in length, has also been coped and finished, and a head-race for improved mill-power has been walled on both sides, and fitted with sluices, so that it can at any time be made available.
The power here created is calculated to range from 70 to 200 horse¬ power, according to the state of tide and flood; whereas the only water-power that had ever previously existed at the same site could not have exceeded 20-horse, and so pre¬ carious does that seem to have been that it was not thought sufficient to induce the proprietors to make use of it for the last, twenty-five years preceding the commencement of our works.
In alluding to the completion of the weirs at the " Cutis," and water¬ way provided through the new salmon cribs in connexion with them, it is very satisfactory to be able to state that the total discharging power afforded at ilus outlet of the whole of the waters of the district has been proved by experience to be amply sufficient in floods, and at the same time to be so regulated as to retain the water above the weirs in dry seasons to the height required for mill purposes and navigation, without at all interfering with the salmon fishery, which, on the contrary, has been vastly improved by the permanent character of the new fixtures erected by the Board.
The above facts, as regards discharge, are the more worthy of mention from the circum¬ stance of the quantity of water passing down the Lower Bann at this point being found to vary from 80,000 cubic feet in summer to 500,000 cubic feet or upwards in time of winter floods.
The weirs designed to cross the river higher up the stream, being proportionate in their length to those at the Ci Cutts," cannot fail io prove sufficient, arguing from the ex¬ perience had at the latter place.
At Lougharts Island the shoal next above the t( Cutts," and distant from it about 14; miles, the portion of navigation channel left untouched at ihe close of 1850 was excavated to the bottom in the season of 1851.
The material was gravel, and though much water had to be contended with, it was easily kept out by steam-power.
The spoil-banks produced by the work of 1851 at Loughan's have been formed level, and soiled, and the slopes of excavation protected by stone-paving.
The cross-dams have been opened, and the river has had a passage through them since September.
From Loughan's to Agivey the river is comparatively deep, and what additional capacity is required is to be had by dredging.
A tributary, called the Glenstall River, which runs into the Bann on the Antrim side near to Agivey, has been deepened and improved from its confluence with the river up to the valuable Glenstall flour-mills, whose 1 ail-race has been thereby relieved from back¬ water to a very important extent, in addition to the benefits affoidcd to the adjoining low lands.
A very large quantity of eel fry was passed up at the ee Cutts," and the take of salmon rather exceeded that of 1850.
This excess, however, may be accounted for by the open season having been extended in 1851 to the lst September; whereas in previous years it closed on 20th of August.
It may be remarked, that the salmon taken in 1851 averaged a greater weight each.
The total weight taken at the "Cutts" in 1850 was 13,089 lbs.,
and in 1851 -13,309 lbs.,
being an excess in favour of last year of 310 lbs.
Considering the universal and gradually increasing depreciation of the salmon fisheries throughout the kingdom of late, rt is satisfactory to observe that the take at the " Cutts " has not diminished, but improved in 1851.
The principal items of work performed during the season on 1st division were :—
Excavation of all kinds --23,790 cubic yards.
Stone quarried and dressed --4,588 cubic feet.
Masonry built --1,363 cubic yards.
With the exception of the swivel bridge at Agivey, dredging alone remains to be done, which bears out the anticipations expressed to that effect in my report to the Board for 1850.
2d or Movanagher Division, 17 miles from, Agivcg Bridge to Kilrea Bridge.
On this division, excavation in the river bed was carried on at two points, one imme¬ diately above " Carnroe " lock, and the other at a shoal called Hegarty's Ford, above the head of Movanagher Canal.
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Lhe »Vow" shoal, near " Carnroe," has been removed to full depth for half the intended breadth; and at Hegarty's Ford tho excavation has been completed, and spoon-and-bag^dredge boats have been kept employed taking out the several cross-dams.
The steam engine which had been placed at " Loughan's " has been removed to (t Carnroe," and there
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