As well as the famous Clyde Steamers there were also smaller vessels on the Clyde such as the Rothesay excursion boats. But most notably there were the Clyde Sludge Boats nicknamed "The Clyde Banana Boats". Just south of the Wee Cumbrae and the Garroch Head lay the dumping ground for the banana boats. In the course of the decades from 1904 to 1998 these boats discharged some 90 million tons of sewage sludge into the five hundred foot deep waters just off Bute. During the war years, with the anti-submarine boom stretching between Dunoon and the Cloch Lighthouse, the sludge was dumped at the entrance to Loch Long, between Baron's Point and Strone Point. The crews continuing to be paid their war risk bonus just as if they had still been sailing beyond the boom to the Garroch Head.

The Clyde sewerage purification scheme was introduced by Glasgow Corporation between 1894 and 1904. In 1904 their first Clyde sludge boat was acquired. After the First World War, convalescent soldiers were given free outings on the Corporation's vessels, and from 1925 this practice was developed considerably. The Dalmarnock of 1925 had accommodation for 70 passengers with a comfortable saloon and dining saloon. Later on the S.S. Shieldhall built in 1954 could carry 80 passengers. She was the last passenger steamer to be built for service on the Firth. These trips on the Clyde Sludge Boats, for organised groups only, were free and gave the opportunity of a day out on the Firth of Clyde to many who would not have been able to afford the fare for the railway steamers, thousands being carried over the years. Despite their lowly calling , the sludge boats were always kept immaculately maintained, and in a smart colour scheme of grey hull, brown upperworks and a yellow funnel.

The S.S. Shieldhall originally spent her working days as one of the familiar "Clyde sludge boats" making regular trips from Greenock near Glasgow, Scotland down the River Clyde past the Isle of Arran, in order to dump treated sewage sludge at sea. Nicknamed the "Clyde Banana Boats" these steamships had a tradition, dating back to the First World War, of taking organised parties of passengers on their trips during the summer, and the accommodation is again being put to good use for cruises out of her current homeport of Southampton.

The 1972-ton S.S. Shieldhall was laid down in October 1954, built by Lobnitz & Co. of Renfrew, Scotland who also constructed the two triple expansion steam engines which are set vertically in a similar way to the much larger engines on the RMS Titanic. She was built on classic lines with a traditional wheelhouse of riveted and welded construction, a straight stem and a cruiser stern. Her length is 268 feet (82 m) and breadth 44 feet 7 inches (13.6 m). Passenger accommodation was provided for 80 passengers. She entered service in October 1955 and was operated by Glasgow Corporation to transport treated sewage sludge down the Clyde to be dumped at sea.

In 1976 after 21 years of service on the Clyde the Shieldhall was laid up, and in the following year was purchased by the Southern Water Authority to carry sludge from Southampton to an area south of the Isle of Wight. Sadly due to rising fuel prices she was withdrawn from service in 1985. Fortunately she was preserved by the Solent Steam Packet Limited, which now operates her as a sea-going excursion vessel based in Southampton. In addition she regularly attends maritime festivals. The M.V. Garroch Head built in 1977 was the last of the Clyde Sludge Boats replacing the S.S. Shieldhall. She made the last sailing with passengers on the 24th September 1998 and closed the service on the 31st December 1998 as new regulations meant that it was impossible to dump waste material at sea. Thus the long tradition of public service was ended as was the regular use of Gaelic by their crews.

This vessel represents a very important part of the commercial and maritime history of the River Clyde. She recalls a period in the history of Clyde when turbine steamers and paddle steamers were a common sight and the leisure-tourist day-tripper industry was of great importance. The "Clyde Steamers" not only gave employment in construction, maintenance, repair, operation and servicing but also brought prestige to their operating areas. The "Clyde Steamer" fleets were well known and people were proud of them. The Shieldhall is one of the best known and loved ships in the "Clyde Steamer" fleet and was one of the Clyde sludge boats that worked alongside the more famous and glamorous "Clyde Steamers".

S.S. Shieldhall (1954)
Website: http://www.ss-shieldhall.co.uk

She is listed by the National Historic Ships Unit as part of the "THE UK NATIONAL HISTORIC FLEET" in the National Register of Historic Ships. This means that she is officially recognised to be of pre-eminent national or regional importance, spans the spectrum of achievement in UK maritime history and illustrates changes in construction and technology. Therefore she merits high priority for preservation in the long term and deserves significant public support.