WHITE'S BRIDGE.

Star (Christchurch), Issue 6962, 28 November 1900, Page 2

WHITE'S BRIDGE.

-$ L . THE ENGINEER'S REPORT. DISCUSSION BY THE SELWYN COUNTY GOUKESCL. ■At the meeting of tihe Sehryn County Coiimcil this morning, White's Bridge formed the principal topic of discussion. Considerable correspondence- on the- matter was read, and the solicitor's opinions on various points were placed before the Council. The South Waimakariri River Board) forwarded the following resolution' : — " That on receiving a written) request irom the Selwyn County Council 'to 'this Board to ,do tile work •necessary to protect t*he south bank oi the rivev ■wvfchin a vadiiis of ten •dhaiws from the east end. of White's Bridge, and on unldertaking to pay the cost <k the same, this Board will supply the Council with, an estimate of ifhe cost, and will be prepared to do the work at the Council's risk, both as regards construction, and maintt&a'ance." The letter was received, And it was decided to nil the Board to furnish an estimate of Itha cost. The South Waimakariri River Board wrote, stating that the Board's overseer recommended! that i'vro large groins should b,e put in about four chains apart at White's Bridge. The 'total cost would be aibout £500, of-wihich £350 was required now. The letter wae received. Mr A. D. Dotison, C.E., reported that ou Oct. 31 "he had examined White's Bridge in 'company with ilr R. Wright, surveyor to the Oust (Road Board. He found that the east end of the span nearest Christchurch !had dropped, the capsule and the shore ends of the floor joists being quite rotten. The ■flood had scoured! away bhe ground tin. front of the pier on which <tQio rotten timbers had bscn resting. He could not ascertain the depth to which the piles were driven, -bijt believed fhej' were 35ft in, length. This being so, fchey were only about 13ft iiii the shingle. He* thought it unsafe to attempt to ibuild "a aiew superstru'eture, and he did udts think the present .superstructure could •be utilised economically! om a new bridge. The iroiferk trusses were the only sound limber, and; might *be used if it were possible to stop the traffic for eight or ten weeks. The traffic over itie 'bridge was large a#d its anaintenance bo inrportamt to the northern districts that it would be a great inco3T€nienice to dose the bridge unless there was no otiher alternative. , He would, therefore, advise the erection of a perfectly new bridge just above the present one, to be built entirely of iron-birk. He also forwarded a plan of a new bridge, suggesting one consisting of eleven, 50ft spans on piers built of four piles each, 'the piles to bs 50ft lomg. The trusses to be douiblc, a nd set in cast-ivon shoes, enabling timber of light scantling; to he used, whidi would foe ea^y to handle. . The long pieces required would bo the .piles. By making the trusses douible, whea renewals were required a defective piecs could fee removed without shoring up the truss or interfering unduly with -Che traffic. He had designed he bridge to be built entirely of ironbaik. A small sufing might hs effected by making the superstructure of kaoiri, but it would not last so lore, and he would reccmraien'd tihe ironibark. He enclosed an estimate of the cost. Mr Dob Eon waited on the' Council, and referred .at length to the state <xf the Ibridge, t stating that the capsules were quite rotten. The bridge was unsafe, and he thought it beyond hops to repair it in anyway. He produced plans of tli© river-bed, and pointed out the danger of the river breaking through the low country and cutting the bridge off altogether. He considered extensive protective works should bo established. The Chairman said that there were various bodies interested in the matter, and he would Suggest they be communicated wifh. It was decided to writs to the bodies interested, and forward to ea«h a copy of Mr Dobson's plan and estima,te, and request an expression of opinion from each.