We aim to replenish more fresh water than we consume in our operations. We will do this by being more efficient in operational freshwater use and effluent management, and by collaborating with others to replenish freshwater in stressed and scarce catchment areas where we operate.
To be water positive by 2035 we have two objectives. Firstly to focus on improving the efficiency of operational freshwater use and effluent management. Initial efforts will be on our major operating sites, prioritized on the basis of current operational efficiencies, water availability risks and catchment conditions. Major operating sites represent 98% of total freshwater withdrawals.
Our second objective is to work through collaboration projects, targeting impactful opportunities to replenish freshwater in stressed and scarce catchments where we operate. This will benefit the environment, communities and industries that share the same water resource, while lowering our water management costs.
Water resources are increasingly under pressure from population growth, economic development, pollution and the changing climate. As stated in our human rights policy we respect the rights to water and sanitation for people who could potentially be affected by our activities, including our employees, contractors and neighbouring communities. And bp is strongly dependent on freshwater too, so we are taking action to become more water efficient.
Currently, we actively manage our freshwater demands in areas of stress and scarcity. Based on analysis using the World Resources Institute Aqueduct Global Water Risk Atlas, four of our 24 major operating sites were located in regions with high or extremely high water stress in 2020, with another four in areas of medium to high water stress. The number of major operating sites in regions with high or extremely high water stress was three, when accounting for our bp petrochemicals and other 2020 divestments.
In 2020 we saw a 2% fall in freshwater withdrawals and a 17% fall in freshwater consumption compared to 2019. This was largely due to the divestment of our Alaskan operation in 2020, the formation of the bp bunge bioenergia joint venture from bp operated biofuels and biopower businesses at the end of 2019 (and no longer being part of bp operations) and a reduction in freshwater use in our bpx energy operations during 2020.
Only 4% of our total freshwater withdrawals and 8% of freshwater consumption were from regions of high or extremely high water stress in 2020 (4% and 5% in 2019 respectively).
There was also improvement in our wastewater treatment performance. The average chemical oxygen demand concentration of the treated water we discharged to the freshwater environment reduced from 45mg/l in 2019 to 38mg/l in 2020. This was due to the wastewater treatment plant upgrades at several refineries.