Table 5. Listeria serotypes collected from irrigation water at three sites each in the Sumas and Serpentine watersheds of the Lower Mainland of British Columbia.

Serotype	Sumas Watershed		Serpentine Watershed
	Recoveries	Sites	Recoveries*	Sites
1/2a	5	2,3	11	1,2,3
1/2b	1	1a	1	2
4b	0	-	10	1,2,3
4c	0	-	1	1

*Occasional recoveries of multiple serotypes were observed at the same site on the same date in the Serpentine watershed.