The owner of one of the Limestone Coast's most popular diving spots has joined a world-famous cave diver in calling for more action to be taken to preserve water levels in the region's sinkholes and wetlands. The concerns raised by Kilsby Sinkhole owner Graham Kilsby and cave diver Richard Harris come after one of the driest years on record in South Australia's south-east. Their concerns are also amid a review of water allocations that has pitted environmentalists against farmers and foresters. Mr Kilsby's family has had a sheep farm at Moorak, just south of Mount Gambier, for more than 130 years and they also offer diving and snorkelling tours at the Kilsby Sinkhole on their property. Mr Kilsby said the water level at the sinkhole has fallen 4.5 metres since 2000 to a record low, including more than 1.5m since Christmas which he attributed to a lack of rain. "We've decided that we're going to completely remove irrigation from the farming property over the next three years," Mr Kilsby said. "It is an awfully big step and I wouldn't expect everyone to give that consideration. Damage hurting tourism The nearby Ewens Ponds has been closed to snorkellers on and off for almost a year because of low water levels, while Piccaninnie Ponds has been closed for two years because of an algal bloom exacerbate by a lack of water flow through the wetlands. Both had been known for their clear water and vibrant aquatic plant life. "Piccaninnie Ponds was one of the best dive sites in Australia. People across the world came there to dive and now it's just a muddy hole," Mr Kilsby said. "Ewens Ponds has got plant life growing at depths where it doesn't grow anywhere else in the world. "Tourism is important, but I think that this is a bigger picture. "It's about everyone in this region — we all rely in same way on the water that's beneath us — we really need to start looking at what we're doing." 'System has essentially died' Dr Harris became known around the world in 2018 due to his involvement in rescuing 12 young soccer players and their coach from a cave in Thailand. He was later named Australian of the Year and is now South Australia's lieutenant governor. He has been cave diving around Mount Gambier since 1986. With cooperation from the South Australian National Parks and Wildlife Service he produced a video showing the situation at Piccaninnie Ponds. "The whole system has essentially died," Dr Harris said. Water allocations being decided The Limestone Coast Landscape Board began work to update the Lower Limestone Coast Water Allocation Plan in 2022 and expects to decide how groundwater will be divided between drinking, agriculture, forestry and the environment in 2027. Dr Harris said while it was not possible to "tell everyone to stop work and down tools", if the aquifer levels got too low "everyone will suffer". "I feel that some very tough decisions are going to have to be made by the landscape board, which is primarily responsible for the water allocation plan," he said. "I think it's time for all these industries that use the groundwater and farm that land to start to think about how we're going to have to adapt to this changing climate, and maybe farm and use the land differently in the future." SA Dairyfarmers Association chief executive Andrew Curtis said it was not clear what was causing the poor water quality in the Piccaninnie Ponds and it should not be "simply attributed to agricultural practice". He said the environment, food production and supplying water for the community should be considered equally when allocating water. "The challenge for the landscape board is to consider all of those issues in working with a limited resource," he said. "As we can see during this drought we just don't have unlimited water. So the challenge is the allocation of it."