M E M O R A N D U M June 16, Response to WetSkills Challenge Case study: Wastewater Treatment Solution for a Growing Village

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1 Cloacina Innovation M E M O R A N D U M June 16, 2014 TO: FROM: RE: Case Owners Rik Huisman, University of Rotterdam Applied Sciences Stacey Kondrakiewicz, University of Wisconsin-Whitewater Saalih Shamead, Ryerson University Marvin van Wijnen, Utrecht University Response to WetSkills Challenge Case study: Wastewater Treatment Solution for a Growing Village We have reviewed the above-noted case study prepared for WetSkills Canada The memo is our proposed solution. Background The Village of Limoges is currently serviced by a two-cell lagoon, rerated to 1,500 m 3 /d (17 L/s). Effluent is discharged to the Castor River during the spring and fall due to the river's intermittent nature. Limoges is projected to grow from 720 households with 27 hectares (ha) of institutional, commercial and industrial (ICI) to 3730 households and 115 ha of ICI in 20 years, though some uncertainty remains in the accuracy of this projection. Its current wastewater treatment capacity needs to be increased to approximately 6900 m 3 /d (80 L/s) to meet this projected demand. A Stage 1 mechanical treatment plant that will increase the capacity to 3500 m 3 at the cost of $8.4 million Canadian Dollars (CAD) has been proposed. Hence the challenge that remains is adding an additional 3400 m 3 /d of treatment capacity that achieves the removal efficiency standards outlined in Table 1. Table 1 Influent and Effluent Values Parameter Influent Design Effluent Objective Limit CBOD5 (mg/l) (97.4%)* 5 Total Suspended Solids (mg/l) (98.0%)* 5 Total Phosphorus (mg/l) (93.3%)* 0.3 Total Ammonia-N (mg/l) Summer (May 1 October 31) Winter (November 1 April 30) (97.3%)* 3 (88.5%)* E. coli (counts/100 ml) n/a Total Residual Chlorine n/a Non-detect 0.02 mg/l (mg/l) * Indicates removal efficiency in terms of percentages. 1 5

2 [2] Approach All conventional and innovative approaches were explored and then evaluated based on the sustainability indicators outlined (Table 2). This table highlights some of the options explored and their relative scores based on the criteria stated. Table 2 Sustainability Indicators Chosen Selection Criteria Centralized Pipelines Decentralized Wetland/Nereda Eco friendly (planet) - Sustains the bio system in the river Able to achieve removal levels - System can perform in all 4 seasons Social acceptance (people) - Acceptance by other stakeholders - Easy to maintain in the future - Low energy demand - Speed to approve and build Cost favours our project over phase 1 Number of Jobs it will generate Flexible system to account for growth Technically feasible Innovativeness (outside the box) Resilience of the system Does it set a model that can be used and implemented in Russell and Embrun and other growing cities outside of Ottawa? 13 of of of of 16 Further details are provided on options from the above Table 2 provided below. Centralized Figure 1 Nereda Cycle (source: (Giesen et al. 2013)) Rather than a conventional mechanical plant a centralized Nereda plant could be built because of its ability to remove the contaminants at a lower energy cost. There is no need for a selector, anaerobic tanks or clarifier which will reduce the building costs and it will have a smaller footprint being 4 times as small a conventional plant. This is why such plants are typically 3/4ths the costs of conventional plants (RoyalHaskoningDHV, 2013). The minimal waste generated in the process, makes it an environmentally sustainable option and easy to operate. It would be a hybrid model whereby Nereda would be used to expand the current wastewater treatment plant (WWTP). The WWTP would be easy to operate and could even be controlled remotely. Furthermore, the waste by-products of the Nereda process can be used for biopolymers, which could be used as a source for prosthetic limbs (Giesen, 2014). Today 20 projects have been started around the world, ranging Brazil, Australia, Poland, France, Germany and the United Kingdom. There also 10 operational plants operating at full scale in South Africa, Portugal and the Netherlands (Giesen et al. 2013). The engineering firms involved in case could be the pioneers of Nereda WWTP in the Canada (licensed from DHV).

3 [3] Pipelines One option considered was to build a pipeline to Ottawa so the wastewater would be treated by the WWTP in Ottawa. This pipe would be 48 kilometres long and downstream according to a digital elevation Model (DEM) of the region. Therefore water would likely not have to be pumped to Ottawa. A pipeline with a diameter of 21 inches would be used because it can carry a flow of 1.8 million gallons per day (mgd). The price of pipeline per meter is $ So with a length of 48 kilometre the pipeline would cost $19,200,000. This cost was determined to be too great, to go into the details of this option, such as costs entailed in having the City of Ottawa treating the water. Another option was to build a pipeline to the nearest river, this is the South Nation River and the pipeline would be 9.75 kilometres. But this river flows only a few months a year so the pipeline would have to be built to another river. The next closest river after South Nation River was the Rideau River. This river flows all year long but the pipeline would be 40 kilometres. 40 kilometres of pipeline would cost $16,000,000 so this option was not deemed viable either as it did not include the possible costs of pumps and further treatment before discharging the water. Decentralized A relevant case study was conducted by the Rocky Mountain Institute in Snowmass, Colorado USA. They studied 8 different cities around the US including Lake Elmo, Minnesota, USA. This city was relevant to the village of Limoges because it is along a similar latitude, and experiences the four seasons, from warm summers to the freezing cold winters. This city was also projected to experience growth similar to Limoges. In the 1980 s, Lake Elmo s population was 5,296 and was projected to grow to 15,200 by In this study, it also mentioned how developers view cluster systems favourably which are systems in which a collection of homes are treated by a mini-wastewater treatment plant system. This configuration allows developers to construct houses and driveways in the best layouts for the neighbourhood creation. According to one developer, it gives you design freedom. In addition the lots are easier to sell to home builders than lots served by individual septic systems (Pinkham et al. 2004, p ). The average cost per household to install a decentralized system in Lake Elmo was $5,689 in 2002 (Pinkham et al. 2004). Accounting for inflation, the cost per household in 2014 is $ 6, So, with 3,010 households ( household that already have WWTP), the cost to implement would be $20,594,721. An issue however is that typical decentralized methods would not be able to meet the standards outlined in Table 1 on a consistent basis (US EPA, 2002). Proposed Solution As can be seen from Table 2 while the scores were close, the winner was a hybrid approach that incorporates both Nereda which is typically a centralized WWTP approach with surface wetlands that have been used both in centralized and decentralized approaches (Crites et al. 2006). While it was not officially disclosed in the case, through further research it was determined that there were already plans in the works to further upgrade the existing facility in stage 2 that would help Limoges reach its 6,900 m 3 /d treatment capacity target at the cost of an additional $15.8 million. Therefore instead of spending a total cost of $24.2 million upgrading a single facility this approach calls for building 3 additional mini plants in strategic locations as the need arises (Delcan, 2011). Therefore, instead of just adding 3,400 m 3 /d of additional capacity, collectively they will add over 5,400 m 3 /d of capacity. While these plants will really be serving as decentralized systems we refer to them as a satellites or clusters even though some may classify them as centralized systems because of the amount of flow they would handle (Barnstable County Wastewater Cost Task Force, 2010). The reason why we chose to refer to the sites as satellite locations is that they are dispersed across the periphery of future development areas (Figure 2). Each location would have three mini Nereda tanks, two that would be operating and one that served as a backup. 1 Source: Hugh Tracy, Parsons

4 [4] Figure 2 Locations of proposed decentralized Nereda + Wetlands (Source: (Delcan, 2011))

5 [5] The advantage of this approach is that one is able to reap the benefits of high removal levels that are achievable by Nereda while at the same time saving money by reducing the overall cost of investment. Unlike conventional centralized systems where the infrastructure is built long before the population reaches the capacity of the system, this approach allows for a more modular design. As such, while it is seemingly more expensive than the current approach this approach may be more economical once one considers the savings based on net present value calculations (Figure 3). Furthermore, since this approach is appreciated by developers as it allows for a more flexible design from their side, they may be more willing to invest in such infrastructure as development charges are typically usually used to build such infrastructure (Pinkham et al. 2004). Furthermore, this approach not only adds greater wastewater treatment capacity but also pays for the cost of an additional wetland park at each site, which could potentially make houses in the area more attractive to potential buyers because of the recreational area it provides. = Centralized = Decentralized = Slow initial growth = Fast initial growth = Mean growth Figure 3 Cost comparison between a centralized versus decentralized approach Innovativeness The innovativeness of the approach is two-fold. Although Nereda is a proven technology that is capable of providing the removal levels necessary to meet the effluent requirements it has never been used in Canada. As such, our decentralized approach makes it easier to be approved to be tested on a pilot scale within Canada, which would make it easier for further Nereda plants to be built here. Furthermore, it has never been paired with wetlands as it is traditionally paired with a sand filter system before allowing its effluent to be released in the environment (Giesen et al. 2013). Technical feasibility While the approach is innovative it is based off of proven technology. Nereda has been used successfully across the world in the Netherlands, England, Poland and South Africa. Furthermore, both centralized and decentralized versions of the system have been built (Giesen et al. 2013). Wetlands on the other hand have been used in Canada to successfully treat sewage as far North as Yukon and the Northwest Territories (CMHC, 2014). If necessary mulch could be used to insulate the wetlands during the wintertime to maintain the system's efficiency (Wallace, 2009). In addition, the soil in the region according to borehole logs is siltly clay and so while the hydraulic conductivity or infiltration rate will be relatively slow it is still possible because the WWTP are serving relatively small areas (Delcan, 2011). Furthermore, Nereda has a smaller footprint than a traditional mechanical WWTP and produces no odour so there should be no issue in placing the system in a residential area. In addition, because wetlands are incorporated into the mix not only will it be possible to meet the standards in Table 1 but also possible to exceed the standards as well as wetlands are a natural purification system on their own and some communities rely primarily on a wetland wastewater purification system (Town of Cobalt, 2014). They are also very effective at removing pathogens in some cases, with removal levels as high as 99% and are also able to remove emerging contaminants such as pharmaceutical compounds as well (Anderson et al. 2013). Furthermore, if for some reason the community wants to return to a conventional system during the construction phase this could be easily done (Study Tour, 2013). It should also be noted that since the areas where these plants would be built are currently open areas it is technically easier to implement in this community because there is minimal existing infrastructure to deal with. Finally, if the

6 [6] village chooses to have the amount of open surface water minimized they also have the option of using subsurface flow constructed wetlands (Crites et al. 2006). Economic Cost The costs for Nereda were calculated both from a very conservative approach and also based on cost curves from the USA. In the conservative approach the cost of a Nereda plant that was used was based on a plant that cost 14 million Euros and was capable of treating 36,000 m 3 /d. Based on those numbers the cost of a single Nereda satellite plant would be $2,055,381 (Study Tour, 2013). Coupled with the costs of wetlands at $146,604/ha and calculating that 6.5 ha of wetlands would be necessary for storage capacity purposes during the dry flow periods and to allow for infiltration the total cost comes to $3,044,960 (CMHC, 2014). While some wetlands are allowed to infiltrate into the ground in Ontario, just in case this was not possible, a pipeline to the Castor River was also considered bringing the total cost to $5,230,942 (Miller, 2010). Using the cost curves the total cost for the first mini Nereda plant would be $9,625,417 (Barnstable County Wastewater Cost Task Force, 2010). However, because there is such as large discrepancy between these two figures it is likely that the total cost would be less than the stage 1 that is currently being proposed. Furthermore, because this is not connecting to the existing system there would be no need to build additional sewer pump systems that would tie into the existing system, as upgrading the existing facility requires, which would save millions (Delcan, 2011). Social and Environmental Context Some areas around Limoges where it is proposed to construct wetlands already have some wetlands so this would help increase the natural habitat area. This could be seen as increasing the atheistic appeal of the area and hereby increasing property values as residents tend to like to live in areas that have a lot of greenery and water features (Figure 4) (City of Bloomington, 2014). In addition, this parkland landscape encourages children to play in this area and helps the village retain its current atmosphere (Pinkham et al. 2004). Furthermore, these wetland parks could also be used to educate the public in a similar manner that is employed in Singapore with displays explaining the importance of parts of the water treatment system 2. The wetlands would also help ensure that at least some of the purified water will recharge groundwater supplies (Crites et al. 2006; Miller, 2010). This is critical as the Village's sole source of drinking water are two wells that draw from an overburden aquifer. Therefore, this system might help prevent the village from having to consider piping water from Ottawa, as it attempts to also increase its drinking water supply in anticipation of projected growth (Delcan, 2011). Based on previous studies a decentralized system owned by the village equates to lower annual payments by village residents which also makes it more attractive to them (Pinkham et al. 2004). Finally, because they may not have to discharge into the Castor River, Limoges would face less opposition from neighbouring villages such as Russell and Embrun. Figure 4 Visualization of Nereda + Wetlands 2 Nick Reid, Ontario Clean Water Agency

7 Works Cited Anderson, J., Carlson, J., Low, J., Challis, J., Wong, C., Knapp, C., & Hanson, M. (2013). Performance of a constructed wetland in Grand Marais, Manitoba, Canada: Removal of nutrients, pharmaceuticals, and antibiotic resistance genes from municipal wastewater. Chemistry Central Journal, 7(54), Barnstable County Wastewater Cost Task Force. (2010, April). Comparison of Costs for Wastewater Managment Systems Applicable to Cape Cod. Retrieved from Cape Cod Water Protection Collaborative Web site: City of Bloomington. (2014). Ecosystem Service 2: Increased Business and Home Values. Retrieved from City of Bloomington Web site: CMHC. (2014). Constructed Wetlands. Retrieved from Canada Mortgage and Housing Corporation Web site: Crites, R., Mddlebrooks, E., & Reed, S. (2006). Natural Wastewater Treatment Systems. Boca Raton: CRC Press. Delcan. (2011). Village of Limoges Development Analysis. Retrieved from The Nation Municipality Web site: Giesen, A. (2014, February). Nereda: New Prespectives for wastewater treatment. Retrieved from Ministry of Regional Development and EU Funds: %20prezentacije/7-RHDHV.pdf Giesen, A., de Bruin, L., Niermans, R., & van der Roest, H. (2013). Advancements in the application of aerobic granular biomass technology for sustainable treatment of wastewater. Water Practice & Technology, 8(1), Miller, G. (2010). 2009/10 Annual Report: Environmental Commissioner of Ontario. Toronto: Environmental Commissioner of Ontario. Pinkham, R., Hamilton, B., Magliaro, J., & Kinsley, M. (2004). Case Studies of Economic Analysis and Community Decision Making for Decentralized Wastewater Systems. Colorado: Rocky Mountain Institute. RoyalHaskoningDHV. (2013). Advantages. Retrieved from RoyalHaskoningDHV Website: Study Tour. (2013). Nereda, Netherlands. Retrieved from Study Tour Web Site: data/case%20studies/case%20study%2023%20- %20Nereda%20Waste%20Water%20Treatement%20Plan%20-%20Netherlands.pdf Town of Cobalt. (2014). Cobalt Constructed Wetland. Retrieved from Town of Cobalt Web site: US EPA. (2002, February). Onsite Wastewater Treatment Systems Manual. Retrieved from US EPA Web site: Wallace, S. (2009, April 13). Constructed Wetlands: How cold can you go? Retrieved from Water Canada Web site:

8 OWN logo Wastewater, why waste it? Wastewater treatment solution for a growing village Rik Huisman, Stacey Kordrakiewicz, Saalih Shamead, Marvin van Wijnen Limoges, ON: Current Situation Systematic Approach Current total households: 720 Projected total households: 3730 Their Solution: Our Solution: Criteria Centralized Wetland/Nereda Able to achieve removal levels Resilience of the system flexible to account for growth Speed to approve and build Nereda + Wetlands Wetlands Improve water quality Recharge depleted aquifer Constant discharge effluent Increase attractiveness of new development Recreational Area Creates habitat for wildlife Educational tool RoyalHaskoningDHV Nereda 4 times smaller area than conventional plants Lower energy consumption (20-30% less) No generation of waste chemicals Compact: no separate clarifiers and aerobic/anoxic/anaerobic compartments Easy to operate, with little mechanical/electrical equipment Capable of delivering excellent effluent quality, removing N and P in one single process. No odour Lower Cost Wetskills-Canada 2014 is organized and supported by: Study case provider(s):