Decarbonizing Biosolids Reuse Through Indigenous, Ecological, and Technological Perspectives

Looking to Indigenous leadership for stewardship of natural resources

We can improve the design of sanitation and wastewater services by considering and integrating Indigenous perspectives. The W̱SÁNEĆ Leadership Council (WLC), a political organization comprised of three W̱SÁNEĆ First Nations, seeks to promote sustainable and equitable development of resources within its territory. It is from this perspective that the WLC is interested in determining the most sustainable and equitable method of managing biosolids from a combined technological, ecological, and sociocultural perspective.

Biosolids, or wastewater treatment residuals, are the organic solid by-products from wastewater treatment (Canadian Council of Ministers of the Environment, 2012). Biosolids management practices impact anthropogenic emissions of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) (CCME, 2009). There are emissions of CH4 and N2O emitted directly from excreta; the emission of CO2 from excreta is considered climate neutral (Haug, 1993). Additionally, there are also emissions associated with the operational system that manages the biosolids for reuse. For example, there can be vehicular emissions associated with the transport of biosolids from the processing facility to the application site (Alvarez-Gaitan, Short, Lundie, & Stuetz, 2016). Biosolids management practices can also impact greenhouse gas sinks; for example, the land application of biosolids can lead to an improved carbon sequestration capacity and production of electricity from biosolid incineration can offset emissions from other electricity sources (Alvarez-Gaitan et al., 2016; Gopalakrishnan, Grubb, & Bakshi, 2017).

The Capital Region District (CRD) in British Columbia is building a wastewater treatment facility to treat the region’s wastewater. The facility’s residual solids will be transported to a Residuals Treatment Facility for processing to a Class A biosolids designation. Class A biosolids are the highest quality standard biosolids that meet strict standards for pathogen, heavy metal, and chemical content (OMRR, 2016). The Residuals Treatment Facility as well as the conveyance lines that transport the sludge are located on the traditional territories of the W̱SÁNEĆ Peoples.

The paradigmatic design approach for wastewater systems - and biosolids reuse - is narrowly focused on technological (i.e. to meet regulations) and economic (i.e. lowest cost) aspects, but a few publications suggest that the engineering design space can be expanded to integrate ecological and ecosystem services aspects including climate change impacts (Trimmer, Miller, & Guest, 2019; Wang et al., 2018). Ecosystem services describe the services provided by natural systems, for example climate regulation, nutrient cycling, and water provisioning (Toffey & Brown, 2020). It is suggested that designing wastewater infrastructure and biosolids management with a holistic technological-ecological approach will advance truly sustainable wastewater management protocols (Wang et al., 2018).

Joni Olsen, the WLC’s CRD liaison, suggested that even a holistic technological-ecological approach may overlook the totally different perspective the W̱SÁNEĆ community has with respect to the natural and sacred world. The WLC has identified a need to develop an engineering design framework towards a long-term decarbonizing use of biosolids that considers technological, ecological, and uniquely W̱SÁNEĆ perspectives. This framework will give the WLC the information needed to engage in discussions with the CRD and thereby enhance W̱SÁNEĆ sovereignty and stewardship of natural resources in the region.

The design of such a framework has manifold climate solution impacts including: 1) an improved understanding of how different biosolids management practices impact ecosystem services including climate regulation; 2) empowering increased Indigenous participation in environmental decision-making; and 3) the development of a wastewater infrastructure co-design framework that can serve as a blueprint towards a more equitable and sustainable change to biosolids management in British Columbia and Canada.

Traditional knowledge (TK) is a “cumulative body of knowledge, practice and belief, evolving by adaptive processes, and handed down through generations by cultural transmission, about the relationship of living beings (including humans) with one another and their environment,” (Black & McBean, 2016). The incorporation of TK into environmental decision-making is recognized to encourage sustainable environmental management and a more holistic understanding of the environment (Black & McBean, 2016). The advancement of climate solutions depends on understanding the sources of emissions and how nature rebalances the climate system (Project Drawdown, 2020). Beyond a quantitative understanding of greenhouse gas emissions sources and sinks, I argue that a TK perspective is essential to the design of a sustainable biosolids management system that results in an improved stewardship of the environment (including the global carbon cycle).

In Canada, there are a variety of options for managing biosolids including land application as a soil amendment, combustion for energy capture, use as a combustion feedstock in cement manufacture kilns, and disposal to landfills (Canadian Council of Ministers of the Environment, 2012). One proposed long-term reuse option for the CRD-produced biosolids is the production of biochar for land application. Biochar is produced via the pyrolysis of biomass, and it mitigates greenhouse gas emissions and can increase carbon sequestration (Stewart, Zheng, Botte, & Cotrufo, 2013). The potential for biochar to mitigate greenhouse gas emissions and increase carbon sequestration depends on the chemical composition of the biochar, the carbon and nitrogen budgets of the soil, and the rate of biochar addition (Stewart et al., 2013). It has been recommended that biochar be added to the “climate change toolkit” (Glaser, Parr, Braun, & Kopolo, 2009). Project Drawdown recommends biochar production as an engineered sink that supports nature’s carbon cycle (Project Drawdown, 2020).

Biochar production represents an example of circular sanitation design. Circular sanitation design reconceives excreta as a resource rather than as a problem, which enables sustainable environmental improvements (McNicol, Jeliazovski, François, Kramer, & Ryals, 2020). There are recent studies that explore the intersection of sanitation and waste treatment with ecosystem services like climate regulation, examine the climate impact of various biosolids management practices using life cycle assessment and footprint methods, but more data are needed to understand the biogeochemistry of sanitation including both sources and sinks and interactions with local to global environmental systems (Gopalakrishnan et al., 2017; McNicol et al., 2020; Trimmer et al., 2019). Currently, there is no research that considers the role of TK and social, cultural, spiritual, and other values in the design of sanitation and wastewater services.

The full participation of Indigenous community members in decision-making around environmental management is a critical part of Canada’s decolonization and reconciliation work (Black & McBean, 2016). I hope that the integration of Indigenous perspectives in the sanitation and wastewater treatment services will result in a simultaneous realization of the important opportunities associated with the reuse of excreta as a resource as well as the capacity of Indigenous stewardship of these resources and others.


Alvarez-Gaitan, J. P., Short, M. D., Lundie, S., & Stuetz, R. (2016). Towards a comprehensive greenhouse gas emissions inventory for biosolids. Water Research, 96, 299–307.

Black, K., & McBean, E. (2016). Increased indigenous participation in environmental decision-making: A policy analysis for the improvement of indigenous health. International Indigenous Policy Journal, 7(4).

Canadian Council of Ministers of the Environment. (2012). Guidance Document for the Beneficial use of Municipal Biosolids, Municipal Sludge and Treated Septage.

CCME. (2009). Biosolids Emissions Assessment Model : User Guide. Canadian Councile of Ministers of the Environment, Winnipeg.

Glaser, B., Parr, M., Braun, C., & Kopolo, G. (2009). Biochar is carbon negative. Nature Geoscience, 2(2).

Gopalakrishnan, V., Grubb, G. F., & Bakshi, B. R. (2017). Biosolids management with net-zero CO2 emissions: a techno-ecological synergy design. Clean Technologies and Environmental Policy, 19(8), 2099–2111.

Haug, R. (1993). The Practical Handbook of Compost Engineering. New York: Routledge.

McNicol, G., Jeliazovski, J., François, J. J., Kramer, S., & Ryals, R. (2020). Climate change mitigation potential in sanitation via off-site composting of human waste. Nature Climate Change, 10(6), 545–549.

OMRR. (2016). Organic Matter Recycling Regulation. Organic Matter Recycling Regulation (OMRR) – Policy Intentions Paper Ministry of Environment – OMRR Review, (September). Retrieved from

Project Drawdown. (2020). The Drawdown Review. Project Drawdown Publication, (March 2020), 104.

Stewart, C. E., Zheng, J., Botte, J., & Cotrufo, M. F. (2013). Co-generated fast pyrolysis biochar mitigates green-house gas emissions and increases carbon sequestration in temperate soils. GCB Bioenergy, 5(2), 153–164.

Toffey, W., & Brown, S. (2020). Biosolids and ecosystem services - making the connection explicit. Current Opinion in Environmental Science & Health.

Trimmer, J. T., Miller, D. C., & Guest, J. S. (2019). Resource recovery from sanitation to enhance ecosystem services. Nature Sustainability, 2(August), 681–690.

Wang, X., Daigger, G., Lee, D. J., Liu, J., Ren, N. Q., Qu, J., … Butler, D. (2018). Evolving wastewater infrastructure paradigm to enhance harmony with nature. Science Advances, 4(8), 1–11.