CV Wastewater Treatment Plant Odour Control

Frequently Asked Questions
December 18, 2013
Comox Valley Wastewater Treatment Plant - Odour Control

Q. What is the early history related to odours at the Comox Valley water pollution control centre?
A. The Comox Valley water pollution control centre (CVWPCC) was commissioned in 1984 and shortly afterwards, the regional district began to receive odour complaints related to plant operation. These complaints tended to be from residents along Curtis Road where odours are more frequent, especially in evenings in the late summer or early fall when certain weather conditions (off-shore wind) prevail. It was determined at the time that the greatest contribution towards odours at the CVWPCC was the long wastewater residence time in the pressurized pumping system from the Courtenay pump station, along with the on-site composting of biosolids at the treatment plant. The regional district worked hard to reduce odours and improve the situation, however the odours persisted and in 1985 the Curtis Road residents committee filed legal action against the regional district. 

Q. What was the outcome of this legal action? 

A. The CVRD negotiated an out-of-court settlement with the Curtis Road residents committee which required that the regional district pay compensation to residents, relocate the compost facility to a remote off-site location and install additional odour treatment at the CVWPCC to capture and treat the most odourous gases from the processing equipment. This work took considerable time to investigate and implement, but by 1997 a new wet chemical scrubber system ($2,000,000) had been installed at the CVWPCC and by 2002 a new biosolids composting facility ($5,000,000) had been constructed at the Comox Valley waste management centre (CVWMC).

Q.  Does the regional district have a policy in place related to odour control? 

A.  In 2006 the regional district implemented policy 5340-00 being the “expenditure of funds for odour control” policy.  In consideration of the significant investment previously made to control odours, the policy set guidelines for the expenditure of future funds for odour control. The policy states that the regional district will not spend further public funds in relation to odour control at the CVWPCC unless:

a)      staff become aware of new technology or enhancements to current technology that would result in a reduction in odours for a reasonable cost;

b)      staff become aware of new operating procedures that could result in a reduction in odours for a reasonable cost;

c)      the level of odour emission is increasing beyond current levels to an extent that creates a materially increased odour level; or

d)      there are modifications to the odour control system required as a result of an amendments to a statute or other enactment. 

Q. What has the CVRD done to maintain odour control from the CVWPCC? 
A. The wet chemical scrubber system at the CVWPCC has been operational for 16 years and has helped to improve odour-related issues both at the plant and in the surrounding community. In addition, operational and maintenance best practices used at the plant consider the effects of odour and attempt to minimize odour within the plant and in the surrounding community. 

Q. What does the CVRD currently do when it receives an odour-related complaint? 
A. From time to time, the regional district does receive complaints from residents adjacent to the CVWPCC.  These complaints are normally received verbally (over the phone) or in writing (email or letter) and tend to be received in the late summer or early fall. The number of complaints is typically less than 10 per year.

The CVRD responds to odour complaints by first determining whether or not the odour issue is related to operational or maintenance issues at the plant. From time to time, changes in plant operation can contribute to increased levels of odour when certain processing equipment is taken out of service for maintenance. If the odour issue does not correspond to specific plant-related operation or maintenance, then staff work closely with complainants to ensure that they understand the history of plant odours and the extensive effort and expense that the CVRD had undertaken in an effort to improve odours both at the plant and in areas adjacent to the plant. CVRD staff routinely invite complainants to the plant to review the operation and odour control equipment that is in place.


Q. What has prompted the regional district to consider additional expenditures in 2014 to address odour-related issues?
A. Under direction of the 2006 policy “expenditure of funds for odour control”, it states that “public funds could be spent if staff become of aware of new control technology or operating procedures that could result in a reduction in odours or when the level of odour is increasing”, in order to better understand the above, the CVRD has allocated $50,000 into the 2014 budget. 

The $50,000 will be used to complete an evaluation of the existing odour control equipment and practices at the CVWPCC, which will include performance testing, an audit of operational and maintenance practices, a review of the latest technologies and the development of a monitoring system to ensure odour control performance. In addition, to ensure odour complaints are consistently managed and monitored, a tracking system will be designed and implemented.  The outcome of this study will inform the CVRD on the next steps. 

Q. What is the expected timeline for the evaluation study and implementation of the monitoring system? 
A. Provided that funding is approved at the end of March 2014, the CVRD will retain a consultant by July 2014 and endeavour to complete evaluation before the end of 2014. The consultant’s final report will be made available once received and reviewed by the CVRD board in early 2015.