On the Severn there is now practically no navigation above Stourport. Much money has been spent on the river since the Severn Navigation Act of 1842; the channel has been deepened and dredged, and, "up to Worcester, at any rate, the river is now one of the best of English waterways." But, in spite of the considerable sums expended on improvements, the traffic fell from 323,329 tons in 1888 to 288,198 tons in 1905, a decline in seventeen years of over 35,000 tons. High water in the river renders it impossible for the larger estuary-going vessels to pass under certain of the bridges, so that, as one witness said, "A vessel may go up when the water is low, and a freshet may come, and the vessel may not be able to get back again for perhaps many days." The Warwickshire Avon, once navigable from Stratford to the Severn, is now navigable only from Evesham, and even from that point "there is hardly any commercial traffic." The Trent is navigable to-day to the junction with the Trent and Mersey Canal, at Derwent mouth, "when there is plenty of water." The report says:-- "The great difficulty on the Trent, in its present condition, is the want of sufficient depth of water in dry seasons; in wet seasons traffic is impeded by floods. The river Trent is a fine river and a most important part of the main route connecting the Midland waterway system and the town and colliery district of Nottingham with each other and with the estuary of the Humber. It appears, for want of necessary {156}works of improvement, to be in an inefficient state for these purposes. There is, at present, no certainty that a barge carrying seventy or eighty tons of cargo from the port of Hull to Newark or Nottingham will arrive at its destination without being lightened on its way. A witness said, 'Very often the traffic in dry seasons is left waiting for two or three weeks on the road between Hull and Newark, which, of course, is a very poor way of getting on with business.'" On the Ouse (York), below Naburn Lock, the conservators find it difficult to keep the channel at its proper depth by reason of the great deposits of floating sand, or "warp," distributed by the tides, the scour of the river being insufficient to carry the warp out to sea. Vessels are at times unable to navigate for several days, obstructive shoals are formed, and the line of the channel is frequently altered. On the Bedford Ouse the traffic on the upper parts of the river has come to an end, and, though there is still a small amount between Lynn and St. Ives, "the river is in many places very shallow and choked with weeds and mud, so that barges are often stopped for days, and the use of steam traction, up to St. Ives, is impossible."