More than £227,000 is needed to complete ongoing works at the NSC.
Tynwald will be asked to approve the funds for the flumes at this month's sitting - taking place next week.
The Department of Education, Sport and Culture says the overspend is because of ongoing problems regarding the leisure pool and flumes.
The facility has been closed since August 2018.
Manx Care reprimanded over former worker's data access failings
Manx Care's been rapped for dragging its heels under data protection laws.
Government announces pay deal with unions
The government says it's reached a pay deal with two public sector unions.
Museum plans memorial for lost aviators
Ballasalla could be getting a monument to flyers and aviators who never made it home again.
Drone investigation suggests radio interference at work
A UK investigator says radio interference may have been behind a drone's strange behaviour in the south of the Island.
MHK questions minimum wage tax and NI payments
How much did minimum wage workers pay into government coffers last year?
Former Montpelier boss faces bankruptcy hearing
The multimillionaire head of a former trust company that went into liquidation could be declared bankrupt this summer.
Commissioners disappointed over end of police drop-ins
Commissioners in Onchan say they're sad to see the end of community police drop-in sessions for the village.
Manx Utilities minds its dam business
Manx Utilities says it's taking on a big project on a dam near South Barrule.
