By By 1878 approximately 50 vessels belonged to Emsworth - rowing boats for fishing within the harbour, and smacks of up to 30 tons and 50 feet in length capable of fishing in more distant waters. A small number of boats were involved in coastal trade with commodities including coal, corn and timber. For its size, Emsworth had a significant shipbuilding industry and the supported manufacturing of sailcloth, fishing nets and rope. Perhaps the most famous Emsworth shipbuilder was J.D. Foster who built cutters and fast deep-water ketches from 1880 onwards. Today, a century later, it is the 'Echo', Foster's fastest and largest cutter with an overall length of 112 feet, for which it is most renowned. It is reputed to have been the largest fishing vessel to have sailed out of an English port.

At the height of successful industry, over three million oysters a year came out of Emsworth to be distributed across the country. At the end of the 19th century half the population of Emsworth earned their living from fishing, oyster dredging or the industries that support the trade, such as boat building. Alas the industry collapsed when the Dean of Winchester died in 1902 and the blame was laid on polluted oysters. Since then the waters have been cleaned-up, but today only a handful of fishermen are still dredging the harbour for oysters.