You may be able to do the repairs with the pool full, **provided every line feeding the work area can be positively isolated**. I’d try that before cutting a pipe with water behind it.

- **Plug the actual pipe openings in the skimmers.** Remove the baskets and use correctly sized threaded winterizing plugs or rubber expansion plugs in the ports at the bottom. Blocking the skimmer mouth can still leave an air leak. Some skimmers have a second port connected to a main drain or equalizer, so identify the connections first. Plug any return jets feeding the repair area too. [Pentair’s winterizing guidance](https://www.pentairpool.com.au/winterising/) and [skimmer information](https://www.pentair.com/en-us/pool-spa/products/white-goods/admiral-s15-s20-skimmers.html) describe these fittings.
- **If you need to lower the water, use a siphon.** A garden hose or airtight pool vacuum hose will work if its discharge end is below the pool’s water surface. Fill the hose completely by submerging it, cover one end, move that end to a suitable discharge location, then uncover it while keeping the intake submerged. Flow stops when the water reaches the discharge elevation or air enters the hose. [Pool water-level guidance](https://old.swimmingpool.com/maintenance/pool-care-basics/pool-water-level/)
- **If the elevation won’t permit enough draining, rent a submersible pump.** That gives you controlled drainage while leaving the existing plumbing intact.

Turn off power to the pool pump before fitting plugs, and keep it off during repairs. **An unisolated main-drain line can continue flooding the equipment area even with the skimmers and returns plugged**; that situation calls for a pool technician.

Avoid substantially draining an inground pool until groundwater conditions have been assessed: groundwater pressure can lift the shell. [Pool & Hot Tub Alliance guidance](https://www.phta.org/pub/?id=546ca8d9-1866-daac-99fb-f7b38202eb2a)