D.—l 7

5

Overlap of Breakwater. —Sir John Coode intended that the south breakwater should overlap the north one by 120 ft. only The overlap at present is 500 ft., and the Board has decided to increase it to I,oooft. Sir John Coode intended the width between the breakwaters to be 400 ft. , they are constructed at 450 ft. at low-water line, and are found to be dangerously narrow for steamers coming in with a heavy swell. The great overlap of the south over the north end of the breakwaters was suggested by shipmasters as a remedy for the difficulties of entering the river in rough weather I should not have thought that this overlap would improve the depth on the bar, and I shall watch the result with much interest, if, however, it causes any serious shoaling of the entrance, the north breakwater must also be extended, and the entrance will then be in a better position than it is now, as the further seaward the breakwaters are the greater will be the average depth of the entrance. One effect of the projection of the south breakwater beyond the north one is seen in the considerably greater depth which the section taken across from wall to wall at the end of north wall has over the section taken from the end of south wall square across towards the north. The contour-lines I have drawn from my soundings show these effects very plainly , and I think it would be useful as a guide in future operations if a thorough marine survey were made from time to time of the water all round outside the breakwaters. Depth of Bar. —In spite of the long absence of floods, I find that the depth of water on the bar not only holds its own, but continually improves. The following table shows that in 1881 the usual depths were from 10ft. to 13ft.; in 1891, the usual depths were 16ft. to 23ft. at low-water spring-tides, and 1891-92 shows a slight improvement over 1890-91.

Table showing the Number of Days each Year the Available Depths for Navigation at Highwater Spring-tides over the Greymouth Bar have been as under for Twelve Years ending the 31st March, 1892.

Cost of Works, —The expenditure on the Greymouth Harbour works is so mixed up with the expenditure by the Public Works Department that it is difficult to ascertain the total cost of the works. The cost incurred by the Harbour Board on account of harbour-works from 1884 to 1892 is as follows :— £ North breakwater 45,719 South breakwaker 56,236 Training-walls 21,575 Wharves 26,931 Dredging .. 6,570 Eaising flood-wall .. 1,232 Plant .. 11,989 Brunner Railway and rolling-stock 20,773 Cobden Bridge 1,079 Land 2,242 Office and furniture .. 2,227 Sundries 1,550 £198,123 Work still to be done. —The works remaining to be done consist of extending the south breakwater 500 ft., the extension of the Goal Creek training-wall which I have recommended, dredging to an uncertain amount, but as may be necessary from time to time, a cradle to repair the dredgingplant, and the cost of supervision. Sir John Coode's plan shows extension of the training-bank above the bridge, but the construction of the bridge has entirely altered the circumstances under which his plan was designed, and I do not see the necessity for any works above the bridge. List of works yet to be done— £ Extension of south breakwater (500 ft.) 26,532 Extension of Coal Creek training-wall 4,200 Dredging (say) 4,000 Dredging in channel to Karoro Lagoon 4,180 Cradle for repairing plant 300 Supervision and contingencies .. .. 1,758 £40,970 The total cost of the works when completed will therefore be £239,093. From this must be deducted the sum paid towards improvements and extra rolling-stock on the Brunner Bailway,

1880-1 1881-2 1882-3 1883-4 1884-5 1885-6 1886-7 1887-8 1888-9 1889-90 1890-li ! 1891-2 I I Under 10ft. 10ft., under 12ft. 12ft., „ 14ft. 14ft., „ 16ft. 16ft., „ 18ft. 18ft., „ 20ft. 20ft., „ 22ft. 22ft., „ 24ft. 24ft. and over. 165 140 57 3 130 143 90 2 16 78 230 40 1 27! 85 134 100 30 13 44 144 124 40 14 75 91 119 64 2 5 57 230 65 8 6 108 105 119 28 1 11 60 146 99 33 15 44 92 133 69 27 20 59 94 88 80 24 13 51 123 112 49 18