To reduce our overall water requirements, we maintain high produced water recycle rates throughout our operations. During 2014, our recycle rates remained above 90% throughout our thermal in situ, polymerflood and waterflood operations. We improved our recycle rates at Kirby South thermal in situ operations by 9 per cent, and at Primrose and Wolf Lake Oil Sands (PAW) thermal in situ operations by 2.8 per cent over the previous year. Our Nipisi light oil waterflood operations maintain a water recycle rate of more than 99 per cent.
In 2014, we also increased brackish water use at our thermal in situ operations. As a result of infrastructure investments at our Wolf Lake Central Processing facility to treat brackish water, PAW’s use of brackish water to generate steam improved 25 per cent compared to 2013, reducing fresh water use. At Kirby South, 64 per cent of the water used to generate steam was brackish. This was a great achievement over 2013, when operations initially required more fresh water for start-up.
In our Southeast Saskatchewan and Manitoba enhanced oil recovery operations, we use water from a brackish aquifer for waterflooding purposes.
At our Horizon Oil Sands operation, our water use management strategies are also proving effective. Fresh water use intensity was reduced by 12 per cent in 2014 compared to 2013, through increased recycling of tailings water and limiting fresh water withdrawals from the Athabasca River to less than one-third of our regulated allocation. We work with other oil sands operators to manage water withdrawals to ensure the ecology of the Athabasca River is protected. Horizon features an on-site water storage pond that holds enough water for up to 30 days that allows us to maintain production in the event of water withdrawal restrictions during the river's low flow periods. Additionally, different water treatment options are being reviewed to further reduce our fresh water consumption.
Canadian Natural’s Septimus unconventional natural gas operations in northeast British Columbia also utilizes produced water from the plant for hydraulic fracturing operations and recycles water to drill subsequent wells.