Melbourne's drinking water and catchment areas put at risk by âsystemic' illegal logging on steep slopes, experts say By national science, technology and environment reporter Michael Slezak Posted 2 AprApril 2021 at 8:03pm Experts say logging on slopes of more than 30 degrees can harm drinking water quality in some areas. ( Print text only Cancel Victoria's state-owned logging company VicForests has put Melbourne's drinking supply at risk by illegally logging on steep slopes in an important water catchment area, according to the government regulator. Key points: Logging on slopes steeper than 30 degrees is banned in some areas protected for drinking water supply The Victorian government's conservation regulator found the government-run VicForests breached this law at two locations