All Seasons Leisure Centre in Water Street was closed to the public due to a faulty chlorine gas sensor on Friday (May 6).
Chorley Council has confirmed a new sensor has been ordered and that it is hoped it will be installed by Monday (May 9).
Coun Alistair Bradley, Leader of Chorley Council, said: “People using All Seasons Leisure Centre may have noticed we have had to evacuate visitors a couple of times over the past week.
“This has been due to the chlorine gas sensor being activated – on each occasion there has not been a chlorine gas leak and we have now identified the equipment as being faulty.
“We have ordered a new sensor that we are hoping to have in place on Monday, which will mean we can then re-open.
“We appreciate people’s patience and hope people understand that everyone’s safety needs to come first.”