February - 2019

Mark Jones with mighty stalagmites in the Road to Hell, Clearwater Cave

The 2018 team who have been in Mulu for 2.5 weeks have successfully concluded their work in the Clearwater Cave System where objectives included a new airflow study project and initiation of a new re-survey programme for parts of the cave where original data has been lost or misplaced. The ambitious objectives were partly achieved but due to inclement weather some elements of the studies had to be suspended for the safety of the team. However, sufficient groundwork was established to allow these projects to be easily picked up and continued on future expeditions.

Even at this early stage the airflow studies revealed interesting data which points to regular patterns including draught reversals ay certain times of the day. This may lead to an indications of the best times to search for new entrances and/or as yet unexplored parts of the cave. Much more work requires to be done but the studies certainly proved the efficacy of the approach and the suitability of the equipment. The expedition is grateful to Gill Instruments Ltd for the donation of sonic anemometers which were complemented by loggers from RPR Ltd, both companies based in Lymington, Hampshire.

Gill Instruments 'Windsonic' anemometer in Illusion Passage in Cave of the Winds

Whilst at Camp 5 a DJI Mavic Pro camera drone was used to search for cave entrances in the Melinau Gorge. Several new entrances were observed and photographed in the Benarat cliffs and whilst it was not possible to get close enough to the Canopy Cave area due to flight time from the C5 launch site this may be achievable from other locations and the drone proved its versatility and usefulness for future reconnaissance work.

As well as these studies a small amount of exploration was possible and a further 800m of new cave was added to the Clearwater System length mainly in the Whiterock section of the cave.

As ever we are grateful to the Sarawak Forestry Corporation for their ongoing support and to the Gunung Mulu National Park for accommodating the expedition at Park Headquarters and Camp 5. Our thanks also to our logistics manager Veno Enar, camp cook Steve and all the boatmen and porters.

Aerial view of the Melinau Gorge from the camera drone