Such a margin of victory seemed unlikely when Woodlands, despite a battling 56 from Duncan Snell, plunged to 104-7 as Jack Hartley (4-47) and Harry Smallwood (3-50) struck.
They were revived by wicketkeeper Usman Salim (34) and captain Swanepoel (31) as a total of 189-9 was posted.
Champions Cleckheaton are just three points behind Woodlands after a 103-run win at Yeadon. Kiwi Elliott Herd took 6-71 for Yeadon but could not prevent Cleckheaton from reaching 203, Mally Nicholson making 74 and Tanzeel Altaf (61).
Altaf (4-43) and captain John Wood (3-14) bowled out the home side for 100 and the result sent them tumbling back into the relegation positions. Oliver Halliday (47) and Jake Wray (46) dominated their side’s innings.
Farsley’s second-successive defeat, a six-wicket reverse against Hanging Heaton, saw them drop to fourth place.
Former Yorkshire opener Joe Sayers (69) and Andrew Duckworth (69no) top-scored as Farsley made 190-4, but their total was passed with some ease by Hanging Heaton as Gary Fellows (66), Joe Fraser (44) and Ben Elvidge (36no) led the way.
Pudsey Congs remain rooted to the bottom and are the only team in the top flight without a win after their 11-run loss at Lightcliffe.
Suleman Khan top-scored with 58 in Lightcliffe’s 183 and followed up by taking 5-32 as Congs were dismissed for 172.
East Bierley climbed out of the relegation positions with a comfortable 45-run win over Morley.