Increasing Water-use Efficiency Through Reclamation and Reuse

Increasing Water-use Efficiency Through Reclamation and Reuse

The recently completed BC Water Conservation Survey conducted by the Ministry of Water, Land and Air Protection and the BCWWA’s Water Sustainability Committee, showed that only five percent of respondent communities utilized water reuse as part of their water management strategies. This is in contrast to many other areas of the world where water reuse is a significant component in overall water management plans. Water reclamation and reuse has been found to be a viable and effective method to conserve valuable resources, and should be given due consideration in B.C. communities.

There are three terms often used interchangeably that refer to the process of utilizing recovered water: reclamation, reuse, and recycling. Reclamation is the process by which wastewater (municipal effluent, rainwater, and stormwater) is collected and treated for the purpose of reuse. Water reuse is the actual utilization of reclaimed water. Recycling is a term used most commonly for industrial operations where water is collected, treated, and put back into the industrial process.

In Canada, treated wastewater is most commonly reused in agricultural, golf course, and landscape irrigation. Only about three percent of B.C.’s wastewater is currently being reused, therefore the potential does exist to greatly expand reuse programs. A good example of an extensive reuse program can be found with the City of Vernon. Annually, it uses one billion gallons of treated wastewater to irrigate 2500 acres of agricultural, recreational, and forestry land. The result of this program is that since 1977, there have been virtually no discharges of the City’s municipal effluent into Okanagan Lake.

Water reuse is also used in some B.C. buildings such as office complexes, schools, institutions, and resorts. Treated wastewater is often used for toilet and urinal flushing, which greatly decreases water consumption. In some cases, 90 percent of a building’s wastewater is reused resulting in significant water savings.

There are many factors involved in the implementation of a wastewater reuse plan. Some things to consider are: design and engineering requirements, economic feasibility, financial considerations, regulatory requirements, environmental impacts, and public acceptance. Standards for wastewater reuse can be found in the Ministry of Water, Land and Air Protection’s “Municipal Sewage Regulation.” This document governs project design, operation, and monitoring. Additional reference and guidance information that can be used to assess the viability of wastewater reuse projects can be found in the Ministry’s “Code of Practice for the Use of Reclaimed Water.”Water reuse has been found to significantly reduce water supply requirements. By incorporating a reuse component into water management plans, a community can greatly increase water-use efficiency. However, each project is different, and all factors must be considered before implementing any reuse scheme. Human and environmental health are of the utmost importance, therefore a cautious approach is prudent. However, the potential gains make reuse projects well worth investigating.