Detail from William Edgeworth’s 1824 Survey showing the cut through the 220yd neck of land at the Mandale Loop and the proposed cut at Portrack.
The Mandale cut cost £9000, it not only shortened the distance from Stockton to the sea, it also increased the depth of water at Stockton Quay from 8ft to 10ft and led to the usage of the Port of Stockton to rise from about 24,500 tons in 1804 to nearly 43,000 tons in 1812. The Portrack cut increased the tonnage even further to 88,000.
With the development and expansion of the coal trade the port of Stockton began to struggle, the water at the quay was not deep enough to take the larger collier briggs therefore in 1828 the Stockton & Darlington Railway Company obtained an Act of Parliament to extend their railway line to the new coal staithes close to the Middlesbrough Farm House where the river was deeper. The staithes were designed by Timothy Hackworth and opened in 1830, the port was named Port Darlington. A new town, Middlesbrough, was laid out to service the port. The export of coal from the river rose from 7,300 tons in 1826 to a peak of 742,000 tons in 1846 (source – The History of the River Tees in Maps. Cleveland & Teesside Local History Society 1990).
The old river now joins the Tees through a culvert just downstream of the barrage.
The Smell of Water 
What were the dates for Mandale Cut & Portrack Cut on River Tees.
When Yarm ceased to be a Major Port on the Tees as did Stockton etc. – Why was there NO removal / reopening of the Original Meandering to return the River Tees to its Original Length?
The Mandale Cut opened in 1810 & the Portrack Cut, opened in 1831. As for the rest, I don’t know.
The port of Stockton though in decline remained open until the 1960s. Restoring the original course of the river has never been suggested, but much has shrunk or disappeared. The world has moved on.
Rest Roring River Tees to its Original Length – Would Definitely REDUCE risks of FLOODING – by Several Billion Gallons of water being More Evenly Distributed (as would Clearing-Out of RUBBLE, RUBBISH etc.&Dredgin of Tees and its Tributaries e.g. Lustrum
Beck (made back to Original Length of Pre-1960s, i.e. One-MILE longer than its present length. +Billingham Beck in section near A1046 – has had large
loads of Bricks ‘Dumped & Left in-situ’ for More than FIFTY-YEARS ! Add to that list the MESS near UNIVERSITY
of Durham/Technical College + From
Yarm to & Beyond ‘Tees-Barrage and
thence Downstream to Teesport & form Employment for many plus making ALL-Sections aforementioned
LESS ‘FLOOD-PRONE’& VERMIN FREE!
-HAVENS
metioned
It would not be reasonably practical to do what you suggest,however some of your comments have a ring of truth about them.