D— 1.

Bridges. During the past year 124 bridges were completed, the total length being 11,106 ft., and a large number are at present under construction. The Board is still faced with the problem of urgent bridge-renewals, which has been accentuated to some extent by the continued increase in traffic. The rate of progress depends, firstly, on the preparation of detailed designs and specifications and, secondly, on the availability of materials. In the matter of design it may be explained that the Public Works Department's staff is working under great pressure and additional qualified staff cannot be procured. With regard to materials, delays have been experienced in connection with the delivery of steel, but it is hoped that the position in this respect will improve. The standard bridge width for important highways is 24 ft., and only under exceptional circumstances, where traffic is relatively low and likely to remain so, is any modification of this standard entertained. The usual practice is to provide footways in addition to the 24 ft. roadway where local circumstances require special accommodation for pedestrian traffic. In order to further assist local authorities in the early replacement of old bridges on main highways under their control it was decided to increase the subsidy for highway bridging from £2 for £1 to £3 for £1. This higher rate applies to work carried out subsequent to the 31st March, 1938. In the last report a description was given of several major bridge works for which contracts had been arranged, and the position regarding those and other structures is shown in the progress report. Elimination of Level Crossings. During the past year almost £300,000 was expended on the elimination of dangerous level railwaycrossings on main highways, bringing the total amount spent by the Board to £400,000 since the present major programme was commenced some two years ago. The following summary shows the position of this programme as at the end of the last financial year compared with the schedule which appeared in the previous annual report: — As at As at 31st March, 1938. 31st March, 1937. Work completed .. .. .. .. .. 50 crossings. 15 crossings. Contracts let and/or work in hand .. .. .. 56 ~ 67 ~ Proposals completed.. .. .. .. .. 5 ~ 7 ~ Proposals in hand .. .. . . . . . . 42 ~ 57 ~ Surveys, &c., in hand .. .. .. .. 38 ~ 36 ~ Investigated and deferred meantime .. .. .. 28 ~ 18 „ 219 200 As explained in the last report, those cases where proposals have been deferred in the meantime generally relate to crossings in boroughs, townships, and other closely built-up areas where interference with property would involve costly schemes. In these localities traffic speeds are usually restricted, thereby minimizing danger to some extent, and automatic warning-devices have been installed. This arrangement allows of immediate attention being concentrated upon dangerous crossings on trunk routes in rural areas where expenditure can be applied towards securing the immediate elimination of a greater number of level crossings. When in due course the rural elimination projects are well advanced, further consideration can be given to closely investigating proposals for dealing with open crossings in built-up localities. Details regarding operations carried out last year are shown in the progress report. The following is a description of a number of typical elimination schemes : — Hopu Hopu.—This crossing, on the Auckland-Hamilton State highway, was eliminated by the construction of an overbridge. The bridge is 108 ft. long, made up of two spans of 54 ft. each, and has pile foundations with heavy wingwalls so that approach fillings would be kept clear of the space required for the railway. A curve of 12 chains radius is built into the bridge. Tirau. —This crossing, located on the Hamilton-Rotorua State highway, was characterized by the railway being on a curve with visibility to road traffic restricted by a curve and a grade in the highway. A subway for road traffic has been constructed, the railway being carried on 55 ft. plate girders on a skew of 34°. The road has been realigned and regraded to give approaches to the subway. Koutu.—This level crossing at Eotorua, also on the Hamilton-Rotorua State highway, is being dealt with by the erection of an overbridge 121 ft. in length, comprising three simple spans of 40 ft., 41 ft., and 40 ft. respectively. The bridge, which has spread footings, provides a roadway 24 ft. wide and is located on a skew of 49§° to the railway. Puha. —At this locality the highway formerly crossed the railway twice within a distance of half a mile, and although the road and rail traffic are not of high intensity there was a particularly dangerous feature in that the railway is in a block cutting adjacent to one of the crossings. The highway has been deviated and kept on the western side, thus eliminating two crossings. Mangamanaia. — This crossing, on the Palmerston North - Napier State highway, is being eliminated by the erection of an overbridge 120 ft. in length and consisting of three 40 ft. simple spans with a 24 ft. roadway. The structure is supported by reinforced-concrete columns on footings and has a skew of 53° to the railway.

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