In spite of recent concerns, Leisureland Pool and Gym are fully open to the public and members and there is currently no plan to close. As the sea swimming season draws to an end, it might be worth thinking about winter training in a warm pool.
In the current environment, many of the Leisureland sessions are undersubscribed. For example the 8am adults only session, when I am there, is often just one or two swimmer per lane, so plenty of room to swim as fast ( or as slow ) as you want.
You can see a full timetable at https://www.leisureland.ie/swimming/public-times-prices/