COUNTY BRIDGES.

Waipawa Mail, Volume LXII, Issue 39, 11 March 1935, Page 1

COUNTY BRIDGES.

REPORT BY ENGINEER. ON CONDITION OF TIMBER STRUCTURES. The County engineer, Mr V. Douglas', submitted, at to-day’s meeting of the Council, the following report on the timber bridges under the control of the Council:— As instructed by the Council, I submit below the first portion of the report on timber bridges in the County. For convenience of reference I have divided the County into three sections:—Section, 1, north of the Waipawa river; section 2, between Waipawa and Tula Tuki rivers; section 3, south of the Tuki Tuki river. This, the first part of the report, deals with Sections 1 and 2 only. The Section 3 j will be presented at the next Council j meeting. | In inspecting the bridges I have eni deavored to estimate the approximate j life of each bridge. This, the Council j will understand, depends on a diversity of circumstances, all of which it is impossible to foretell. I have omitted all culverts of span six feet and under. For the purpose of this report I have made the following assumptions :—l. Traffic will remain substantially as it is to-day; 2, no unusual floods or scour will occur; 3, no unusual loads will be carried. Many bridges require repairs. In some cases quite considerable repairs. I have endeavored to estimate the cost of such repairs as will become necessary within the next five years. When, in my opinion, the cost of such repairs would exceed the interest and sinking fund on a new bridge for a period of five years I have recommended that a new bridge be built. In many cases when the repairs outlined have been carried out the bridge will be good for many more years’ i service. In any event, a further comprehensive inspection should be made in five years’ time. In some cases though the bridge itself is in fair order other considerations may call for a new structure. Attention has been called to such cases. I will now proceed to an individual examiuation, report and estimate of probable expenses in the next five years for individual bridges:— SECTION I. 1. Silverstream Bridge.—Span 16ft., width 17ft. Lately reconditioned. Good for ten years. This bridge, however, is on a heavily trafficked main highway and consideration of replacement may arise before the period mentioned. 2. Bridge by Smith’s, Otane- Argyll road.—Span 15ft., width 14ft. Decking replaceable in two years, £24; two l 16ft. 12 x 12 stringers replace in one year, £2O; £44. Bridge then good for ten years. 3. Bridge by McCartin’s.—Span 25ft., width 13ft. —Decking replaceable in five years, £36; two 25ft. stringers 15 x 10 replace in one year, : £32 10s; £6B 10s. Bridge then good for ten years. 4. Bridge by Hamilton’s. —Span 25ft, width lift. Twenty-five per cent, decking replaceable in one year, £9; one 25ft. stringer 15 x 10, immediate replacement, £l6 ss; £25 ss. There is a possibility of scour on this bridge, but if this does not occur the bridge is good for seven years. 5. Bridge by Bainbridge’s, College road.—Span 15ft., width 13ft. In good order for twenty years. 6. Stringer bridge by McCartin’s.— Span 25ft., width 13ft.. One 25ft. stringer 15 x 10 immediate replacement, £l6 ss. Bridge then good for ten years. 7. Truss bridge by McCartin’s.— Span 32ft., width 10ft. 6in.—so per cent decking replaceable two years, £lB. 8. Truss bridge near Argyll school. —Span 49ft., width 12ft. This bridge is unsafe on one abutmeni. The centre upright has sheared off completely, and there is danger of the abutment collapsing. Certain other small repairs are necessary. Repairs to abutment, and general, £3O. Bridge then good for ten years. 9. Bridge, Argyll road. —Span 26ft., width 13ft. —This bridge has been propped at centre of span on timber props which will need replacing within five years. Ten per cent, decking replaceable in two years, £4 10s; two

26ft. stringers 15 x 10 replaceable in tlnee years, £32 10s; replace centre props on five years, £25; total, £6l. These repairs will make the bridge good for ten years. A new bridge would cost £350 to £4OO. It is arguable whether a new bridge would not be cheaper. 10. Mangaonuku bridge.—This bridge was redecked last year. Certain repairs and replacements will preserve it for six or seven years, but it is reaching the limit of its useful life. Repairs required within five years —Replacing various, £2O; three 25ft. stringers 15 x 10, £4B 15s; one pier replacement, £3O; one pile replacement, £10; total, £IOB 15s. 11. Two-mile Creek Bridge.—Replacement shortly, £6OO. 12. Bridge near Campbell’s, Tikokino.—Span 15ft. This small bridge is in poor order, but traffic over it is so light that it may last for many years. The abutments are insecure and may be scoured out. I Suggest that it is repaired as necessary with secondhand-timber, £lO. 13. Bridge near Tikokino Hall. — Span 18ft.—In good order but light structure. Safe for five years if traffic does not unduly increase in weight. 14. Black’s bridge, Gwavas. —Span 27ft., width 12ft. —Fifty per cent, decking replacement in four years, £lB. Good for eight years. 15. Tikokino bridge.—Span 30ft. One stringer in bad order. One abutment completely collapsed, and trimmed up temporarily. Decking in bad order. Bridge should be replaced, £6OO. 16. Motor bridge.—Span 24ft., width lift. —This bridge is in very good order and will last for ten years, but it is very badly located and it might be advisable to consider the provision of a new bridge for this reason alone. 17. Butler’s bridge, Maraekakaho road.—For replacement, £4OO. 18. Moorhead’s bridge.—Length 147 ft., six span, width 13ft. —Bridge is in very good order except the following:—New abutment cap, £10; new stringer, £l6 ss; £26 ss. As far as condition is concerned this bridge with the above repairs is good for twenty years. However, it is not capable of bearing the standard P.W.D. loading for single-way bridge, and the addition of one extra stringer per span would be necessary. This would cost approximately £IOO. 19. Bridge, Haggerty’s road. — Span 22ft., width 13ft. Good order and safe for ten years. 20. Bridge.—Span 12ft., width 12ft. Good order and safe for ten years. 21. Bridge, Brown road.—Span 31ft., width 13ft. In good order and safe for fifteen year's. 22. Bridge by Black’s, Woods road.—Span 19ft., width 13ft. One new upright. Bridge then safe for ten years. 23. Rumble’s bridge, Kereru road. —Length 355 ft., width 7ft. The whole bridge is in good order except that a new abutment is required at one end immediately, cost approximatey £35. This bridge is safe for 15 years, but can only carry light car traffic. 24. Motor bridge.—Length 28ft., width 7ft. 6in. This bridge is in poor order and shauld be replaced, £4OO. 25. Bridge at Addis’.—Length 70ft., width 13ft. Thirty per cent, of decking replaceable in three years, £3O. One abutment (on ground eill) may be undermined in two or three years, otherwise bridge is good for 15 years. 26. Bridge by Vesty’s, Mathieson’s road. —Length 12ft, width lift. Ground cill replaceable in one year, £lO, otherwise good for ten years. 27. Motor bridge.—Length 22ft., width 12ft. Good for ten years with light traffic. 28. Motor bridge.—Length 12ft., width 10ft. Good for ten years. 29. Summersby’s bridge, Holden’s road.—Length 74ft.. width 13ft. Good for fifteen years. 30. Makarora bridge (truss bridge). —Length 128 ft., width 10ft. 6in. In good order except decking, of which 15 per cent, replaceable in two years, £24. Otherwise safe for ten years. 31. Douglas’ Cutting bridge.— Length 132 ft., width 12ft. Two piles replaceable in two years, £2O. The abutment at Wakarara end is on a ground cill and there is a possibility of scour, which should be watched, and which may necessitate protective

works. Otherwise bridge good for ten years. 32. —Bridge, North Block road. — Span 21ft., width lift. 6in. Ten per cent, decking replaceable, £3. Two uprights in abutment require immediate replacement, £5; one new stringer required, £lO. With these repairs bridge good for five years. 33. Bridge, Carson’s road. —Span 55ft., width lift. New stringer required, £ls. Bridge good for ten years. Total part 1., £3673. SECTION 11. 34. Waipawa traffic bridge.—Approximately 16 spans will require redecking in the near future. While this is being done some of the stringers may be trimmed. One new stringer is required. Approximate cost: Decking, 22,500 super, feet at £3, £675; new stringer, £1; £690. Beyond this the bridge appears in good order, though it is possible that a more permanent structure will be required by the growth of traffic before the life of the present bridge has expired. 35. Mate bridge.—Length 123 ft., width 17ft. 6in. New ground cill required within two years, £ls. The bridge shojild then be good for ten years, except that a stringer replacement may be necessary. 3'6. Hobin’s bridge.—Length, 23ft.. 6in. 25 per cent, decking replaceable in two years, £9. Otherwise good for ten years. 37. Waipawa river bridge (Fern-hill-Takapau main highway).— Length 883 ft., width 10ft. mn. Seven concrete piers balance 1.8. piles all in good condition. Running plank repairs, £25. In good condition and safe for fifteen years. 38. McLennan’s bridge.—Length 50ft., width 13ft. Two stringers definitely gone, two or three others doubtful. Decking needs 20 per cent, replacement. Advise reinforced concrete deck or steel girders, £3OO. 39. Onga bridge.—Length 129 ft., width 12ft. Requires new abutment pile cap, £lO. Otherwise good for ten years.

40. Tuki Tuki river bridge.— Length 566 ft., width 12ft. Decking 10 per cent, replaceable in five years, £75. Bridge safe for ten years. 4*. Motor bridge near Worsnop’s (S| inghill road). Length 36ft., wic!:li Oft. Immediate repairs to abutment necessary as in imminent danger of scour, £3O. This is a very ligh: bridge and may need replacing for reasons other than the life of is : tructure, which is good for fire yea s.

4:1 Bridge by Waters’. —Length 2411., width 10ft. 20 per cent, decking' replaceable in five years, £6. Otherwise good for seven years. 43. Bridge, McLeod’s road.—Span, 30ft., width 13ft. Replaceable, £4OO. 44. Bridge, Pettit’s Valley road.— Length 24ft., width 12ft. In good order; life ten years. 45. Carter’s bridge, Fairfield road. —Length 20ft., width 10ft. 6in. Clearance between bottom of stringer and ground only 12in. One stringer gone. Suggest leave and replace by pipe culvert when necessary. 46. Bridge by Jamieson’s, OngaWaipukurau road.—Length 25ft., width 15ft. The timber in this bridge is in good order but the abutments, which are in ground level. Cills are liable to scour, which may occur at any time. Advise leave till scour takes place. 47. Bridge, Lindsay road. —Length 12ft., width 12ft. In good order for fifteen years.

48. Bridge.—Length 14ft., width 14ft. There is a possibility of scour but otherwise the bridge is good for fifteen years. 49. Bridge.—Length 22ft., width 13ft. Good for fifteen years. 50. Bridge, Scenic Reserve road. — Length, 13ft., width 13ft. Good for ten years. Total part H., £lll4.