The deepening of the river at the Broomielaw had led to a gradual undermining of the foundations of the old bridge, which was situated close to the principal landing-place. A little above it, was an ancient overfall weir, which had also contributed to scour away the foundations of the piers. Besides, the bridge was felt to be narrow, inconvenient, and ill-adapted for accommodating the immense traffic passing across the Clyde at that point. It was, therefore, determined to take down the old structure, and Build a new one; and Mr. Telford was called upon to supply the design. The foundation was laid with great ceremony on the 18th of March, 1833, and the new bridge was completed and opened on the 1st of January, 1836, rather more than a year after the engineer's death. It is a very fine work, consisting of seven arches, segments of circles, the central arch being 58 feet 6 inches; the span of the adjoining arches diminishing to 57 feet 9 inches, 55 feet 6 inches, and 52 feet respectively. It is 560 feet in length, with an open waterway of 389 feet, and its total width of carriageway and footpath is 60 feet, or wider, at the time it was built, than any river bridge in the kingdom.
[Image] Glasgow Bridge
Like most previous engineers of eminence—like Perry, Brindley, Smeaton, and Rennie—Mr. Telford was in the course of his life extensively employed in the drainage of the Fen districts. He had been jointly concerned with Mr. Rennie in carrying out the important works of the Eau Brink Cut, and at Mr. Rennie's death he succeeded to much of his practice as consulting engineer.
It was principally in designing and carrying out the drainage of the North Level that Mr. Telford distinguished himself in Fen drainage. The North Level includes all that part of the Great Bedford Level situated between Morton's Leam and the river Welland, comprising about 48,000 acres of land. The river Nene, which brings down from the interior the rainfall of almost the entire county of Northampton, flows through nearly the centre of the district. In some places the stream is confined by embankments, in others it flows along artificial outs, until it enters the great estuary of the Wash, about five miles below Wisbeach. This town is situated on another river which flows through the Level, called the Old Nene. Below the point of junction of these rivers with the Wash, and still more to seaward, was South Holland Sluice, through which the waters of the South Holland Drain entered the estuary. At that point a great mass of silt had accumulated, which tended to choke up the mouths of the rivers further inland, rendering their navigation difficult and precarious, and seriously interrupting the drainage of the whole lowland district traversed by both the Old and New Nene. Indeed the sands were accumulating at such a rate, that the outfall of the Wisbeach River threatened to become completely destroyed.
Such being the state of things, it was determined to take the opinion of some eminent engineer, and Mr. Rennie was employed to survey the district and recommend a measure for the remedy of these great evils. He performed this service in his usually careful and masterly manner; but as the method which he proposed, complete though it was, would have seriously interfered with the trade of Wisbeach, by leaving it out of the line of navigation and drainage which he proposed to open up, the corporation of that town determined to employ another engineer; and Mr Telford was selected to examine and report upon the whole subject, keeping in view the improvement of the river immediately adjacent to the town of Wisbeach.
Mr. Telford confirmed Mr. Rennie's views to a large extent, more especially with reference to the construction of an entirely new outfall, by making an artificial channel from Kindersleys Cut to Crab-Hole Eye anchorage, by which a level lower by nearly twelve feet would be secured for the outfall waters; but he preferred leaving the river open to the tide as high as Wisbeach, rather than place a lock with draw-doors at Lutton Leam Sluice, as had been proposed by Mr. Rennie. He also suggested that the acute angle at the Horseshoe be cut off and the river deepened up to the bridge at Wisbeach, making a new cut along the bank on the south side of the town, which should join the river again immediately above it, thereby converting the intermediate space, by draw-doors and the usual contrivances, into a floating dock. Though this plan was approved by the parties interested in the drainage, to Telford's great mortification it was opposed by the corporation of Wisbeach, and like so many other excellent schemes for the improvement of the Fen districts, it eventually fell to the ground.
The cutting of a new outfall for the river Nene, however, could not much longer be delayed without great danger to the reclaimed lands of the North Level, which, but for some relief of the kind, must shortly have become submerged and reduced to their original waste condition. The subject was revived in 1822, and Mr. Telford was again called upon, in conjunction with Sir John Rennie, whose father had died in the preceding year, to submit a plan of a new Nene Outfall; but it was not until the year 1827 that the necessary Act was obtained, and then only with great difficulty and cost, in consequence of the opposition of the town of Wisbeach. The works consisted principally of a deep cut or canal, about six miles in length, penetrating far through the sand banks into the deep waters of the Wash. They were begun in 1828, and brought to completion in 1830, with the most satisfactory results. A greatly improved outfall was secured by thus carrying. the mouths of the rivers out to sea, and the drainage of the important agricultural districts through which the Nene flows was greatly benefited; while at the same time nearly 6000 acres of valuable corn-growing land were added to the county of Lincoln.
But the opening of the Nene Outfall was only the first of a series of improvements which eventually included the whole of the valuable lands of the North Level, in the district situated between the Nene and the Welland. The opening at Gunthorpe Sluice, which was the outfall for the waters of the Holland Drain, was not less than eleven feet three inches above low water at Crab-Hole; and it was therefore obvious that by lowering this opening a vastly improved drainage of the whole of the level district, extending from twenty to thirty miles inland, for which that sluice was the artificial outlet, would immediately be secured. Urged by Mr. Telford, an Act for the purpose of carrying out the requisite improvement was obtained in 1830, and the excavations having been begun shortly after, were completed in 1834.
A new cut was made from Clow's Cross to Gunthorpe Sluice, in place of the winding course of the old Shire Drain; besides which, a bridge was erected at Cross Keys, or Sutton Wash, and an embankment was made across the Salt Marshes, forming a high road, which, with the bridges previously erected at Fossdyke and Lynn, effectually connected the counties of Norfolk and Lincoln. The result of the improved outfall was what the engineer had predicted. A thorough natural drainage was secured for an extensive district, embracing nearly a hundred thousand acres of fertile land, which had before been very ineffectually though expensively cleared of the surplus water by means of windmills and steam-engines. The productiveness of the soil was greatly increased, and the health and comfort of the inhabitants promoted to an extent that surpassed all previous expectation.
The whole of the new cuts were easily navigable, being from 140 to 200 feet wide at bottom, whereas the old outlets had been variable and were often choked with shifting sand. The district was thus effectually opened up for navigation, and a convenient transit afforded for coals and other articles of consumption. Wisbeach became accessible to vessels of much larger burden, and in the course of a few years after the construction of the Nene Outfall, the trade of the port had more than doubled. Mr. Telford himself, towards the close of his life, spoke with natural pride of the improvements which he had thus been in so great a measure instrumental in carrying out, and which had so materially promoted the comfort, prosperity, and welfare of a very extensive district.*[3]