The Solent's sheltered natural harbours, double tides and inshore waters made it an ideal location for a ports industry to develop. Activity centres on the privately-owned Associated British Ports' (ABP) Port of Southampton and Portsmouth Commercial Port, which is owned and managed by Portsmouth City Council. Cowes Harbour is the main port for the Isle of Wight, and the only location on the Island with deep-water channels capable of handling bulk-cargo carrying ships.
The twentieth century has seen a progressive growth in the scale of port operations in both Portsmouth and Southampton, associated in many cases with reclamation of intertidal land. The expansion of the ports industry is driven by trends in the world market for shipping, which are essentially governed by market forces, the demands of the ship operators, and the supply within the ports. Competition within the UK ports industry and with Northern European ports is intense. The main trend driving the development of the Port of Southampton is the buoyant market in containerised goods - particularly from the Far East, and the increase in the maximum size of the container ships (the post-Panamax vessels).
Cowes Harbour is the major port of entry for commercial shipping trading to the Isle of Wight. Approximately 600,000 tonnes of cargo are handled annually including such commodities as fuel, oil/petroleum, stone, shingle aggregates, timber, grain and general cargo. Ships of up to 100 metres (330ft) in length and with a draft of up to 5.4 metres (17ft 9in) use the port and mainly berth at Kingston or Medina Wharves.
ABP Southampton is the harbour authority for the Solent and manages one of the busiest ports in the UK. The Port of Southampton is the UK's number one export port, handling £40 billion of exports every year including 90 per cent destined for countries outside the EU. The total trade handled by the Port is worth some £75 billion. The Port of Southampton serves as the UK's number one port for automotive exports, providing British manufacturers with essential access to international markets. The Port is also home to the UK's second largest container terminal and each year handles around one million containers. The Port's critical role has been cemented by more than £280 million of investment over the past 5 years, including more than £50 million in brand new state-of-the-art vehicle export facilities. Southampton is also the UK's number one cruise port, with over 500 cruise calls each year bringing two million passengers. In addition, the Port hosts some three million ferry passengers travelling to and from the Isle of Wight.
Portsmouth International Port is the second busiest cross channel ferry port; the Continental Ferry Port accounts for 80 per cent of the Port's business and is served by passenger and freight ferries sailing to the Isle of Wight, continent and the Channel Islands. Portsmouth City Council has owned the Port since 1839, and it is the most successful municipal port in the UK. During 2010 a new passenger terminal was constructed.
Goods passing through the port include fruit and vegetables, fertiliser, ballast, oil, grain, steel, timber and vehicles. The port also increasingly serves cruise vessels.
Portsmouth Naval Base is preparing for the arrival of two new aircraft carriers post 2016 and contributes £1.6bn of output per annum.
The Port of Southampton differs from Portsmouth Commercial Port in the extent of its harbour authority powers within the Solent. ABP is the statutory harbour authority for the port of Southampton, whereas the harbour authority for Portsmouth Harbour and the Eastern Solent is the Queen's Harbour Master (QHM). ABP and the QHM co-operate in administering shipping movements within the Eastern Solent with ABP taking a co-ordinating role. The harbour authority role encompasses responsibility for the navigational safety of all vessels, including the maintenance dredging of channels to advertised depths, navigation marks, hydrographic data, and control of developments which would affect hydrography by issuing harbour licences.
ABP, Portsmouth International Port and Cowes Harbour Commissioners are the designated Competent Harbour Authorities (CHA) for the Solent. All pilotage of commercial ships is undertaken by pilots licensed by the respective CHA. There are close liaison arrangements between the three CHAs and QHM Portsmouth over pilotage and navigational safety matters. The smaller harbour authorities within the Solent carry similar responsibilities for ensuring navigational safety and close working relationships exist between them and the larger authorities