They would not have considered the impact on the countryside since that was a concept unknown to 18th century people, but they did see the advantages of a canal to transport goods. The bisection of farms was a matter easily dealt with by the building of bridges. The canal was approved by Act of Parliament on 30th April 1793.
Work began at both ends of the canal immediately but it was to be some years before the "navigators" came to the middle section in Wolverton. The greatest challenge at Wolverton was the passage across the River Ouse. The original plan provided for four locks on the Southern bank and five locks on the Northern bank but in 1799 the engineer had second thoughts and proposed an aqueduct instead. However, because this project would add a further year of building they went ahead with temporary locks anyway. You can still find the remnants of these on the river bank.
With these in place the canal opened for traffic in the autumn of 1800. Work started on the aqueduct two years later. The contractor, interestingly enough, was Thomas Harrison, the land agent for the Radcliffe Trust and resident of Wolverton House. It is doubtful that he had previous experience of engineering works on this scale but the Canal Company did award him the contract. The aqueduct was built with three arches to support a wooden trunk which was lined with clay to prevent leaks - which it did not. Boats began to use it in August 1805 but it seemed to be a perilous structure from the start. A few months later part of the embankment slipped. Repairs were effected but the Company Architect was not satisfied. Arguments about who was at fault went back and forth between Harrison and the Canal Company until February 1808 when the aqueduct spectacularly crashed overnight.
Thomas Harrison still insisted that he was blameless and the fault lay with the men who had built the aqueduct. The Canal Company sued and took matters into their own hands. They built a temporary wooden trunk in April 1808 so that traffic could resume and commissioned a permanent structure. Stone piers were built and an iron trunk was ordered from the Ketley Iron Works in Shropshire to span the piers. This time they got it right, and in January 1811, the "Iron Trunk" was opened. Next month it will have been in continuous service for 200 years.
Harrison was taken to court and found liable despite his protests and damages were set at £9,262 - a considerable sum of money in those days, but one, which Harrison was readily able to pay.
The aqueduct was not without its consequences. The Ouse was always liable to flooding but in 1823 there was a great flood which even reached Wolverton House to a level of 17 inches above the floor. A civil engineer brought in some years later concluded that the aqueduct was partly to blame because it restricted the flow of water through the piers at high spate. It was not the only reason; the mill race was also a cause.
Before the railways the canal operators more than recovered their investment, but they continued to be of importance in the commercial transport of goods. When I was a boy narrowboats, usually in pairs were still a regular feature, often carrying coal, but by 1960 commercial traffic was gone and leisure craft were increasingly using the waterways.
There were quite important wharves at Old Stratford, by The Galleon at Wolverton and by the New Inn at New Bradwell. Gradually these ceased to function. The presence of the canal and its links to the sea made it possible for the enterprising Edward Hayes to establish his bat building business at Stony Stratford. See this post on Edward Hayes.
In some ways the construction of the canal prepared Wolverton folk for the greater changes which were to come 40 years later with the railway line, and it was in part due to the presence of the canal that the London and Birmingham Railway Company decided to build their engine repair shop at Wolverton.