Updated August 2019
In the Alberta Water Use Performance Report, we look at
In situ oil sands projects use water in the form of steam and require more water per barrel of oil equivalent (BOE) during the first few years of their lifecycle. These projects recover oil by injecting steam into reservoirs so that bitumen viscosity is reduced to a point where it can flow. During the heating process, the steam injected typically stays in the reservoir for a few years before it returns to surface as an emulsion with oil. Some projects inject steam with additives such as gas or solvents to improve oil recovery with less steam and lower pressure.
As in situ projects become fully operational, they require less water per BOE, as the amount of water produced at surface is approximately the same as the amount of steam injected. Near the end of the life cycle, mature projects often transition to gas injection and reuse as much of this produced water as their water treatment facilities will allow. This lowers the amount of steam that's needed and in turn reduces the amount of make-up water needed.
Mature projects that have operated for 10 years have average intensities of 0.15 barrels of nonsaline make-up water per BOE produced. By comparison, projects that have operated for a year have an average water use intensity of 1.76 barrels of nonsaline make-up water per BOE produced.
What is "make-up" water for an in situ oil sands project?
Make-up water is nonsaline or alternative water that is added to replenish the water that is retained within an oil sands reservoir and is not returned to surface. It also supplements recycled water, as some water cannot be treated any further for reuse and must be disposed of as wastewater. Sources of make-up water for in situ can be nonsaline (i.e., lake, river, rain or snowmelt runoff, groundwater) or alternative (i.e., saline groundwater, oil sands process-affected water from neighbouring mines).
Every in situ project is different; there is no single way to determine which projects use water most efficiently. Factors to consider include a reservoir's quality, how much water a company recycles, and a company's ability to access alternative water sources. Project age is another factor that influences water-use efficiency.
In situ operators used nearly 25 per cent of their nonsaline water allocation in 2018.
The map shows where in situ operators are using nonsaline water as a make-up source in Alberta. Zoom in to reveal more.
Total Water Use
In 2018, nearly 258 million cubic metres of water was used to produce over 563 million barrels of oil equivalent from in situ operations. Of the total water used, almost 86 per cent of the water was recycled; the remaining 14 per cent was make-up water from nonsaline or alternative sources.
Although water use and hydrocarbon production have been increasing since 2014, almost all of the increase in water use is because of increased recycling by in situ operators (86 per cent in 2018 from 84 per cent in 2014).
In 2018, almost 35 million cubic metres of make-up water was used for in situ operations, with nonsaline water accounting for about 50 per cent, and alternative water sources accounting for 50 per cent.
Overall, make-up water use for in situ operations has been relatively steady, with only incremental increases since 2014. The ratio of nonsaline water use to alternative water use has remained relatively consistent over that period. This is likely partially related to limits on water disposal imposed by Directive 081: Water Disposal Limits and Reporting Requirements for Thermal In Situ Oil Sands Schemes.
Water-use intensity refers to the amount of water in barrels used to produce one BOE. In 2018, in situ oil sands projects used almost 18 million cubic metres of nonsaline water (25 per cent of all water allocated for in situ oil sands projects) to produce over 563 million BOE—meaning that for every BOE produced, 0.20 barrels of nonsaline water was used. When accounting for rounding, this is a 4 per cent improvement over the previous year, and an improvement of about 11 per cent over the past five years. These short-term trends illustrate a commitment to produce more bitumen with less nonsaline make-up water. Incremental improvements are likely to continue as operators use more alternative make-up water and enable their operations to recover more oil with less steam.
In 2018, 11 of the 25 operating in situ projects decreased their bitumen production, which caused some projects to increase their annual water-use intensities. External forces such as low bitumen prices, pipeline apportionment issues, and curtailment affected this production decrease. Without these forces, water-use intensity for the in situ sector may have decreased to a greater extent.
The water for operating in situ projects needs to come from somewhere—but suitable alternative water sources are not available at all project locations, and many older projects have not been designed to treat saline water. Before Directive 081: Water Disposal Limits and Reporting Requirements for Thermal In Situ Oil Sands Schemeswas implemented, some projects were designed without the ability to even recycle water. However, as priorities have shifted over the years, most projects have made significant efforts to increase their recycled and alternative water use without compromising the nonsaline water resources in the province.
Below, you will see a map showing the location of nonsaline make-up water sources for in situ oil sands production in 2018. The map can be modified to show a scheme subtype, company, project, or water source (surface waterbody or aquifer) of interest.
Water Use Performance by Project
All oil sands projects require a combination of nonsaline and alternative sources. In the in situ sector, recycled and alternative make-up water use has been steadily increasing since 2003, with a significant increase following the release of Directive 081 in 2012. After the directive's release, more projects were designed with the capacity to recycle water. In 2018, 92 per cent of in situ operators recycled water and reused it as steam in their bitumen extraction process.
In addition, in 2006, after the release of the Water Conservation and Allocation Guideline for Oilfield Injection, a lot of projects started using alternative make-up water (saline groundwater or process-affected [tailings] water from nearby oil sands mines) instead of nonsaline water. As of 2018, 56 per cent of in situ operators used alternative make-up water.
In the following figures, you will see water use performance by in situ project, scheme subtype, oil sands area, company, project, and hydrocarbon production.
Water Use by Volume
The amount of water needed for each in situ project changes over the course of its life cycle. Typically, more make-up water per unit of bitumen produced is needed during the initial start-up phase (the first two-to-four years of its life cycle) to heat the reservoir. Once the project reaches a steady state, it is able to recycle and reuse the majority of the water coming back with emulsion; very little make-up water is used per unit of bitumen produced. For this reason, most projects quickly transition from using mainly make-up water sources to using mostly (more than 80 per cent) recycled water. This is why it makes sense to compare projects' water use by age as opposed to calendar year.
Water-use data is available between 2003 and 2018. Since fewer than ten projects have more than ten years of operational life, the industry average is not calculated past that point.
Below, you will see the breakdown of total water volume for in situ projects for a year, scheme subtype, oil sands area, company, project, or hydrocarbon production cohort of interest. By selecting a scheme in the first chart, you are then able to view how the in situ project of interest performs over time (by year since first steam injection) and the breakdown of its total water use (by calendar year).
Nonsaline make-up water-use intensity has been decreasing on an annual basis. As of 2018, the in situ sector has improved its make-up water-use intensity by over 70 per cent since 2003. On average, in 2018, the in situ sector required only 0.20 barrels of nonsaline make-up water for every BOE of bitumen.