The college planned to create a hardship fund to subsidise or pay in full rugby related costs for students.
McBrydie said funds raised would go towards ensuring that money would not stop their boys playing rugby.
"Money shouldn't be a reason for students to miss out on all the awesome things sport has to offer.
"That's also why we picked the Mud Challenge as a fundraiser - as the name suggests, it'll be a challenge, it will be exhausting and it will probably be uncomfortable, but we fully expect everyone to cross the finish line with a massive grin on their face."
The main 6km course will take competitors across mudflats near Pahoia Domain, through paddocks and channels.
It is restricted to people over 16 because of a river crossing and "extreme mud" in the boggy snake obstacle.
Anyone can enter the shorter 3km loop, which will be the second half of the course and will still have lots of muddy challenges.
People can enter as a social or competitive team of three for $110 or as an individual for $40. Entry to the shorter loop will be $15 per person.
Spot prizes will be awarded throughout the day, including for best-dressed competitors.
Enter online through the taurangamudchallenge.co.nz website or at the main office of the college.