A 1915 outbreak of swine fever gives clues as to where the piggeries were. See London Gazette which mentions the same piggeries as this notice by Surrey County Council:
This notice mentions five piggeries in Mitcham affected by swine fever:
Westfield Farm, Western Road, in the occupation of John Cornwall
Seale’s Piggeries, off Lewis Road
Reader’s Piggeries, off Lewis Road
Batsworth Road Allotment Garden
Church Road Allotment Garden
Westfield Farm can be found in the 1915 Kelly directory as being just north of Fountain Place on the west side of Western Road.
The location of the Lewis Road piggeries can be obtained from the 1915 Kelly’s Directory, as it describes the properties as from Church Road and after Oakwood and Ashtree Avenues. The 1910 OS Map can be used with an overlay to see theses avenues today and as there are only two properties on Lewis Road in 1910, the piggeries can be identified.
This photo of pigs in the 1950s was taken in Batsworth Road and the tanks in the background are on the W.J. Bush factory.
RESTRICTION ON MOVEMENT TO OR FROM CERTAIN PREMISES MITCHAM.
NOTICE IS HEREBY GIVEN that by an Order dated 17th March. 1915 (No. 9585) made by the Board of Agriculture and Fisheries and which came into operation on the 24th March, 1915, the Board have imposed restrictions on the movement of Swine from or to the undermentioned premises in the Parish of Mitcham:— 1. The premises known as Westfield Farm Western-road, Mitcham. in the occupation of John Cornwall. 2. The premises known as Seale’s Piggeries, situate off Lewes-road, Mitcham. 3. The premises known as Reader’s Piggeries, situate off Lewes-road. Mitcham. 4. The premises known as the Batsworth-road Allotment Garden and the Church-road Allotment Garden. Copies of the above mentioned Order may obtained at this of this upon application. By Order. T. W. WEEDING. Clerk of the Council.
Local people would say that you should never buy pork with the rind cut off, as that’s where the ‘diamond’ blotches of swine fever would show. Without the rind, you couldn’t tell if the meat was infected. Source: my father, who also kept pigs at the Batsworth Road site in the 1950s.