In a report presented to the Board of Admiralty in August 1814, John Rennie highlighted three specific limitations upon the value of Chatham as a dockyard, all of them requiring immediate attention [84]. The three problems to which he referred were the difficulties and hazards of navigating the Medway, the shallowness of the dry docks and the poor arrangement of the yard. To correct these shortcomings, over the next fifty years, the Admiralty expended a great deal of time and effort. Rennie's all-encompassing and immediate solution, the transformation of Limehouse and Chatham Reaches into a massive enclosed basin for the mooring of ships in a controlled level of water, was never adopted. However, it was an idea to which he returned in 1821 [105].

The hazards of navigating the river primarily resulted from an inadequate depth of water and the existence of numerous treacherous shoals. Furthermore, there was considerable evidence to show that the problem was getting worse [95]. Identified as a major factor in the process of shallowing was the existence of Rochester Bridge and its immense stone supports (or starlings). This reduced the flow of the current and inhibited the natural scouring of accumulated silt [96]. Much attention was, therefore, given to a complete replacement of the Bridge [93, 99]. Other factors, either actual or potential, were also examined and commented upon throughout the period [93, 117, 118]. Despite the partial rebuilding of Rochester Bridge, the reshaping of the dockyard wall [87, 117, 120] and the removal of a number of further obstacles that contributed to a reduction in the flow of the Medway, it was ultimately the utilisation of more efficient dredgers [89, 112, 119] and use of paddle steamers for the towing of ships [116] that made the greatest contribution to improved navigation of the Medway. However, the problem still existed in 1857 [120].

The second problem to which Rennie alluded in his submission of 1814 was the shallowness of the dry docks and their poor state of upkeep. At the time the Admiralty agreed that all dry docks should undergo a thorough repair and improvement. At the same time, Rennie suggested the construction of a series of new docks. The Admiralty accepted the need for one new dock. This was built between Nos 2 and 3 docks [88]. Although preparatory work began in 1816, the first stone was not laid until March 1818 [98].