One of the hottest summers on record led to dry ground and low water levels in the lake at Hesley Wood Scout Activity Centre in Chapeltown, where the event was due to take place onÂ October 13.
Â Dependent on rainfall between now and next spring, the event has been re-arranged forÂ Saturday, March 30, 2019.
Planned to raise funds for children and young adults supported by Bluebell Wood Children's Hospice, the re-scheduled event will include a three-kilometre Family Mud Madness for anyone over 11, and a five-kilometre Mud Madness for entrantsÂ aged 17 and over.
Yuri Matischen from event organisers MLS said: 'We'd like to apologise to all the entrants for postponing Mud Madness to next March, but we need to make sure that the event has the right conditions.
'The depletion of the lake and the very dry nature of the woods mean we wouldn't have been able to create the muddy experience promised.
'The event will continue to support Bluebell Wood and all entries can either be transferred to the March event or refunded.'
Helen Mower, Head of Fundraising, Bluebell Wood, said: 'We're hoping for a normal winter and spring-like conditions for next year's event, soÂ our supporters can make magical muddy memories and raise money for families facing unimaginably tough times.'
MLS is contacting all entrants and the venue and entry fees will remain the same for 2019. The early bird offer has been extended to 31 December 2018, withÂ entries already made at full price to be refunded in line with the early bird fee.
Early bird tickets are available at Â£16.50 for 11-16 year olds and Â£25 for 17 years plus. From 1 January 2019, entry fees will be Â£17.50 for 11-16 year olds and Â£30 for over 17s.
To book your place on Mud Madness please visit:Â www.myraceentries.co.uk/mudmadness/EntryForm.aspx
For more ideas to help 290 children and young adults with life-shortening and life-threatening conditions, visitÂ www.bluebellwood.org