Energy and Water Nexus: a complex interdependent system.

When thinking of saving water, the first thought that comes to mind is to take a quick shower or to close the tap when brushing the teeth. But, have you ever thought that you could save water by turning off the lights?

Water and energy are highly interconnected and interdependent systems. Water is used in almost all phases of the energy chain, for both fuel and electricity production, and energy is necessary to provide water extraction, treatment, transport and heating or cooling. It is estimated that the energy sector is responsible for 10% of all global withdrawals and water services counts for 4% of the global electricity consumption (EIA, 2016).

Figure 1. Water and Energy Nexus (US Energy Department, 2014a).

Water for Energy

Water is required for fuel production and processing, including fossil, nuclear and biofuel, as well as electricity generation such as thermoelectric, hydropower, nuclear and renewable technologies. Water usage for energy production can be expressed as water withdrawals or consumption. Water consumption is the water that is evaporated, transpired or incorporated into crops’ biomass on biofuel production, being removed from the immediate environment. Water withdraw is the volume of water extracted and returned to the water source, sometimes in lower quality, to be used again by other consumers or by the natural environment (U.S. Department of Energy, 2014).

Table 1 below presents the global water withdrawals and consumption by energy sector. Power generation is responsible for the largest water withdrawals (88%), while primary energy production is the largest consumer (64%). Cooling processes of thermoelectric plants (fossil fuels power stations) are the major contributors for both withdrawals and consumption, in which once-through cooling systems require large withdrawals but less consumption and the recirculating systems consume more water by evaporation and require less quantity of water. The second largest consumer and the third major contributor for water withdrawals is the biofuel production. Water is withdrawn for irrigation and is consumed by evapotranspiration processes, being incorporated into the crops. Although biofuels are considered renewable sources, it represents a huge impact on water usage. This aspect needs to be evaluated when planning the energy matrix of a country (IEA, 2016).

Table 1. Water withdrawals and consumption for energy production, 2014 (IEA, 2016).

In 2013, approximately 60% of Canadian water bodies withdrawals, 38 million cubic metres of water, were used to thermal power generation (Environment and Climate Change Canada, 2016). Although the country has a huge hydroelectric park, thermals still represent 20% of the Canadian power generation source, particularly on the colder regions of Saskatchewan, Nunavut, Northwest Territories, Alberta and Nova Scotia (Natural Resources Canada, 2016). Improving the efficiency of these plants represents a great opportunity to save water in Canada.

Energy for Water

The energy required for each step of water systems relies on site-specific conditions including topography, distance from the water source to the customers, quality of raw water, level of treatment required, losses and inefficiencies. Pumping is the most energy intense step and is involved in most of the processes, from extracting to distribution, including treatment.

Figure 2 shows the amount of energy per cubic meter required by some water processes, and the global energy consumption in the water sector. In 2014, a total of 820 terawatt-hours (4% of the global electricity consumption) were used for water and wastewater services (EIA, 2016).

Desalinization and wastewater treatment are the highest-intensity energy users, but they do not currently represent the largest consumers. However, considering population growth and climate change predictions leading to lower surface and groundwater availability, wastewater reuse and desalinization techniques tend to become more widely used worldwide, leading to an increase in the total global energy required for water supply.

Figure 2. Energy required by water processes per cubic meter (left) and global energy consumption in the water sector (right) (EIA, 2016).

The more the water is treated and the further transported, more energy intensity it becomes, and more water is consumed to provide this energy. Although water and energy resources are interconnected, they are usually managed separately. Considering though a scenario of scarcity, this paradigm needs to change.

Planning together, the US example

Future infrastructure development requires strategies that optimize natural resources consumption, adopting a systems thinking approach and integrating teams and plans. Recently, some countries such as the US have been making progress in this area.

In 2012, after a drought that limited water availability and constrained the operation of some power plants, the US Energy Department created the Energy-Water Nexus Crosscut Team. The group’s actions include developing research and technologies; sharing datasets; integrating models to inform decision-making; harmonizing policies; and enhancing public dialogue to improve water and energy usage. In 2014, was published the report The Water-Energy Nexus: Challenges and Opportunities, defining the following six strategic pillars to address the water-energy nexus (U.S. Department of Energy, 2014):

1. Optimize the freshwater efficiency of energy production, electricity generation, and end-use systems;

2. Optimize the energy efficiency of water management, treatment, distribution, and end-use systems;

3. Enhance the reliability and resilience of energy and water systems;

4. Increase safe and productive use of non-traditional water sources;

5. Promote responsible energy operations with respect to water quality, ecosystem, and seismic impacts and

6. Exploit productive synergies among water and energy systems.

Based on these pillars, a range of actions has been set, since costly initiatives as the development of new technologies and robust computational models, to simple measures such as to reduce waste, which can represent a huge economy. According to the USEPA (2018), municipalities can save from 15% to 30% of the water and wastewater plants operating costs by incorporating energy efficiency practices. It includes planning intermittent processes to run during off-peak hours, installing soft starters to reduce energy used by pumps or even turning off the lights. Similarly, energy systems can reduce water withdrawals by reducing leaks and improving cooling systems through the implementation of closing loops and heat recovery.

The US case represents an example of a strategy to optimize water and energy systems’ efficiency. Their initiatives may become a role model for other countries to face the challenges of managing water and energy in a scenario of scarcity.

References

Environment and Climate Change Canada, 2016, Canadian Environmental Sustainability Indicators: Water Withdrawal and Consumption by Sector. Consulted on day Month, year. [online]. Available at:

www.ec.gc.ca/indicateurs-indicators/default.asp?lang=en&n=5736C951-1 [Accessed on November 30, 2018].

EPA, 2018, Energy Efficiency for Water Utilities. [online]. Available at:

https://www.epa.gov/sustainable-water-infrastructure/energy-efficiency-water-utilities [Accessed on November 30, 2018].

IEA, 2016, World Energy Outlook 2016: Water-Energy Nexus. [online]. Available at:

https://www.iea.org/publications/freepublications/publication/WorldEnergyOutlook2016ExcerptWaterEnergyNexus.pdf [Accessed on November 30, 2018].

Natural Resources Canada, 2016, Electricity facts. [online]. Available at:

https://www.nrcan.gc.ca/energy/facts/electricity/20068 [Accessed on November, 29, 2018].

U.S. Department of Energy, 2014, The Water-Energy Nexus: Challenges and Opportunities; U.S. DOE: Washington, DC. [online]. Available at:

https://www.energy.gov/downloads/water-energy-nexus-challenges-and-opportunities [Accessed on November 30, 2018].

US Energy Department, 2014a, Ensuring the Resiliency of Our Future Water and Energy Systems. [online]. Available at:

https://www.energy.gov/articles/ensuring-resiliency-our-future-water-and-energy-systems [Accessed on November 29, 2018].

December 8, 2018

How the Netherlands ‘keeps its head above water’

The Netherlands is one of those countries who lives up to its name as being a ‘lowland’. 26% of the country is located below sea level, another 29% is susceptible for river floats, which makes the Netherlands highly susceptible for sea level rise.[1] However, for the past 65 years, the Netherlands has managed to prevent disastrous floats thanks to the construction of the Deltaworks.

55% of the Netherlands is susceptible for floods due to sealevel rise

The year 1953 marks the turning point in the Dutch water management system. A heavy storm from the northwest in combination with a spring tide lead to the greatest natural disaster of the 20^th century. The dikes in Zeeland, Zuid-Holland and Noord-Brabant were not strong or high enough to deal with the seawater rise of 4.55 m. A total of 1,836 people lost their lives, 4,300 homes were destroyed and 187,000 farm animals did not make it. The total damage cost was estimated to be $ 8.2 billion dollar.[2]

The current deltaworks establishd in zeeland – The Netherlands

To prevent such a disaster from ever happening again, the Dutch government invested $ 7.8 billion in the Delta works. The Deltaplan got set-up only 20 days after the North Sea Flood of 1953. The main priority was to improve safety in and around the flooded areas, but one should not forget about the economic benefits of open rivers and what would happen to the environment of the rivers when they would be closed off from the sea. The Western Schelde is the only access route to the port of Antwerp, whereas De Nieuwe Waterweg is an important access route to the port of Rotterdam. So how do you keep the rivers open for ships and trade and keep the river environment stable, but also guarantee the safety of people living near and in these flood areas?

Since the Delta committee had as number one priority to keep people save, they first closed waterways that were not important for the ports of both Rotterdam and Antwerp. In these river mouths, they designed dames, barriers and sluices. For the Western Schelde and De Nieuwe Waterweg, the committee decided to not put any of these structures in the river mouths, instead they reinforced the on-land dikes. This way, the ports of Antwerp and Rotterdam remained easy to access.

Eastern Schelde storm surge barrier (oosterscheldekering)

The Eastern Schelde storm surge barrier distinguishes itself from many of the other barriers since the system can be opened. An open barrier is less appealing than a closed dam since it is a lot more expensive, but a closed dam in this area would have negative effects on the fishing industry and the river environment. A total of 62 sluices, which would only be closed in case of storms, are installed to allow as much salt water flowing through as possible to preserve the healthy environment in the Eastern Schelde and the suitable fishing conditions. [3]

The water management system resulted into more benefits than only increased safety. The fresh-water excess created due to the closed dams could be transported to the Ijssel lake to improve the water conditions there. Moreover, the transportation between the different islands of Zeeland became easier since roads were constructed on top of the barriers and dams. Even tough some nature reserves have been damaged by the change in water conditions in the Delta area, new nature reserves have emerged as well. The influence of the Deltaworks on the river environment however is still unknown.

We can conclude that the planning of the Deltaworks depended on several factors such as safety, economy and environment. Due to the large scale of the Deltaworks, namely 700 km of dikes, and the many different factors that played a roll, the Deltaworks took from 1953-1997 to complete. This includes both planning and construction time. The Deltaworks are a great example of systems thinking and adapting to a changing climate. The success of the Deltaworks teaches us that it is possible to balance safety, ecosystem services and economic services, and that is what environmental stewardship is all about.

Used sources:

[1] https://www.pbl.nl/dossiers/klimaatverandering/content/correctie-formulering-over-overstromomgsrisico

[2] https://www.rijkswaterstaat.nl/english/water-systems/protection-against-water/the-flood-of-1953/index.aspx

[3] http://www.deltawerken.com/Deltaworks/23.html

November 29, 2018

How can green infrastructure be implemented in coastal engineering to promote coastal resilience?

Human coastal populations are steadily increasing and make up over 70% of the world’s population, yet are increasingly vulnerable to the threat of climate change induced extreme weather events and sea-level rise. The Intergovernmental Panel on Climate Change predicts a worst-case sea level rise of 0.59m by 2100, but new studies suggest this value may be exceeded in half the time. Regardless of the predicted values, the future effects of climate change on coastal areas will be seen through fisheries and marine habitats, local economies, water resources, increased frequency and intensity of storm events, increased coastal erosion, and increased flood risk. It is imperative to mitigate the effects of climate change where possible by building resilience into coastal communities, including employing strategies for shoreline protection and flood prevention [1]. Increased resilience provides the ability to adapt to change and recover from disruptions from an economic, environmental, and social perspective [2].

Traditional coastal engineering strategies approach the issue of coastal protection with hard, engineered structures to disrupt sediment transport and mitigate flooding. While these built structures may protect the shoreline, they may also have unintended consequences such as the destruction of natural habitat, proximate erosion, and biodiversity alterations and loss [1]. These unintended consequences provide the opportunity for alternate solutions to coastal protection which are sustainable, reliable, and cost-effective while addressing the threat of accelerated sea level rise due to climate change and the minimization of the effects of hard engineered structures on local ecosystems [3].

In this blog, green infrastructure refers to “natural and semi-natural areas with other environmental features designed and managed to deliver a wide range of ecosystem services” [4]. Ecosystem services refers to the benefits humans gain from healthy ecosystems. The integration of green infrastructure in coastal protection can offer shoreline erosion mitigation and foster healthy ecosystems, which provide ecosystem services.

Effective Strategies

An effective strategy to implement green infrastructure into coastal engineering is the development of a hybrid approach to coastal protection. A hybrid approach applies systems-thinking to integrate both hard engineering and green infrastructures and addresses each options strengths, challenges, and effects. Hybrid engineering structures address the limited capacity of natural ecosystems during extreme events and the economic and social costs of hard engineering. As the depth of knowledge on in the interaction between hard engineering and green infrastructure increases, the opportunities for innovative hybrid solutions will increase [2].

Building Materials and Design Considerations

The integration of natural materials in the design of coastal protection can include “sand, sand-fill, wetland plants, oyster reefs, aquatic vegetation, stones, and coir fiber logs” [2]. Using a combined approach of coastal engineering and ecosystem engineering allows for the use of local ecological species to compliment engineering solutions to achieve coastal resilience. For example, oyster beds, mussel beds, willow floodplains, and marram grass can be used to trap sediment and attenuate waves [3]. Simultaneously, hard engineering structures can be designed to better meet the needs of local ecological species and enhance ecosystem functioning by providing a more suitable habitat [2] [3]. Another example of a hybrid approach is the adaptation of dikes and dams to enhance ecological habitat, ecosystem functioning, and sediment precipitation [2] [3]. Further, the construction of artificial structures to support the restoration of shellfish reefs or coral reefs can build coastal resilience by providing ecosystem services of wave attenuation and erosion mitigation [2].

Figure 1 – A planted marsh with a rock sill [7].
Source: National Park Service, Coastal Adaptation Strategies Handbook.

Interdisciplinary Communication

A key component of effective design of hybrid systems is interdisciplinary communication between involved parties, including engineers, ecologists, First Nation communities with traditional local knowledge, and project stakeholders.

Precautions

There is no universal solution for improving coastal resilience as all shorelines are unique, so many different design strategies must be considered to improve coastal resilience. Since very little data is available, the observation of previous studies and projects is important to learn which approaches are most successful in different locations and circumstances. It is widely understood that more research is needed to further develop strategies for building coastal resilience into future hybrid projects [2].

Research must be done to determine the efficacy and unintended consequences of designs, including the effects of the construction of the design. Likewise, it’s important to ensure the effects of the solution have been considered on a temporal and spacial scale, meaning the unintended consequences of the design have been considered in the long term and also for nearby ecosystems [1].

Implementation, Policy, and Tools

As more information is gained, developments can be made in policies, zoning, design codes, and decision and planning tools [2]. Strategies to integrate green infrastructure into coastal engineering design include “building the case for natural coastal protection” and bringing green infrastructure “into the mainstream decision process” [6].

By improving research and building better models which account of combined risks, a clearer understanding of the magnitude of coastal protection from green infrastructure can be used to make decisions. Likewise, the valuation of ecosystem services from green infrastructure can inform economic arguments for decision makers. The development of policies, planning tools, and decision-support tools which consider the benefits of green infrastructure will bring hybrid approaches to coastal engineering into the mainstream development planning process [6].

Challenges of Hybrid Designs

The major challenge associated with the application of hybrid designs to coastal engineering is the lack of data, testing, and design practices. Due to the unique nature of coastlines, there is no clear design code or even best practice guideline to inform which solutions may be best in a situation [3]. Further, hybrid designs do not provide the same degree of ecosystem services as strictly green infrastructure applications may provide, and may still produce negative impacts on local ecology. Also, since the hybrid projects are relatively new, the permitting process may be more difficult than for traditional, established infrastructure projects.

The existing data that is available suggests the application of solely green infrastructure is best for low energy shorelines [6]. In situations where engineering criteria, local site conditions, or hydro-dynamic conditions necessitate the use of strictly hard engineering solutions, small ecological considerations can be applied to the design such as modified structures which enhance biodiversity habitats. While the solution may be small, the consideration of local biodiversity may mitigate the ecological impact of habitat destruction during construction and aid with community acceptance and permitting [3].

Figure 2 –Pots creating habitat on a seawall [8].
Source: M. Browne and M. Chapman Ecologically Informed Engineering Reduces Loss of Intertidal Biodiversity on Artificial Shorelines

Benefits of Hybrid Designs

A hybrid approach combines the best components of built and natural infrastructure for coastal resilience. In addition to coastal protection, a hybrid approach combines the cost-effectiveness and ecosystem services of a green infrastructure approach with the known capacity and smaller space requirements of a hard engineering approach [2]. Ecosystem services may include water quality improvements, habitat creation or preservation, wave attenuation, sediment capture, vertical accretion, erosion reduction, and mitigation of storm surge and debris movement [5].

From a cultural perspective, the potential green spaces included in a hybrid design provide low maintenance, pleasing aesthetics and can serve as social gathering points in communities, contributing to physical and mental wellness of community members [2]. Similarly, the stewardship and enhancement of coastal ecosystems can play a role in the well-being of coastal resource dependent careers [6].

Figure 3 – Images of natural ecosystems and built infrastructure [2]. Photo Credits: NOAA for all images except Dunes (credit: American Green), Sea Wall (credit: University of Hawaii Sea Grant), and Levee (credit: J. Lehto, NOAA).

Summary

Coastlines are places of great economic, social, and environmental value, but are also vulnerable to flooding and erosion from extreme weather events and sea level rise. As coastal engineering solutions are applied to address this vulnerability, it is important to consider environmental stewardship to provide solutions that meet the needs of both society and the environment. Natural ecosystems can serve as green infrastructure alongside hard engineering infrastructure as a hybrid approach to coastal resilience. However, more research is required to better understand the opportunities for effective implementation of such hybrid approaches and the value of ecosystem services provided. This information can be used to further develop planning tools, policies, and engineering best practices to promote the successful use of green infrastructure and ecological considerations in coastal engineering applications as the demand for coastal resilience increases.

References

[1] Chapman, M. and Underwood, A. (2011). Evaluation of ecological engineering of “armoured” shorelines to improve their value as habitat. Journal of Experimental Marine Biology and Ecology, [online] 400(1-2), pp.302-313. [Online]. Available at: https://www.sciencedirect.com/science/article/pii/S0022098111000736 [Accessed 25 Nov. 2018].

[2] Sutton-Grier, A., Wowk, K. and Bamford, H. (2015). Future of our coasts: The potential for natural and hybrid infrastructure to enhance the resilience of our coastal communities, economies and ecosystems. Environmental Science & Policy, [Online]. 51, pp.137-148. Available at: https://www.sciencedirect.com/science/article/pii/S1462901115000799 [Accessed 25 Nov. 2018].

[3] Borsje, B., van Wesenbeeck, B., Dekker, F., Paalvast, P., Bouma, T., van Katwijk, M. and de Vries, M. (2011). How ecological engineering can serve in coastal protection. Ecological Engineering, 37(2), pp.113-122. [Online]. Available at:
https://www.sciencedirect.com/science/article/pii/S0925857410003216 [Accessed 25 Nov. 2018].

[4] Silva, J., Wheeler, E. (2017). Ecosystems as infrastructure. Perspectives in Ecology and Conservation, 15(1) pp.32-35. [Online]. Available at:
https://www.sciencedirect.com/science/article/pii/S1679007316300767 [Accessed 26 Nov. 2018]

[5] “Understanding Living Shorelines”, Fisheries.noaa.gov, 2018. [Online]. Available: https://www.fisheries.noaa.gov/insight/understanding-living-shorelines. [Accessed: 25- Nov- 2018].

[6] Spalding, M., Ruffo, S., Lacambra, C., Meliane, I., Hale, L., Shepard, C. and Beck, M. (2014). The role of ecosystems in coastal protection: Adapting to climate change and coastal hazards. Ocean & Coastal Management, [Online]. 90, pp.50-57. Available at: https://www.sciencedirect.com/science/article/pii/S0964569113002147 [Accessed 25 Nov. 2018].

[7] National Park Service, Coastal Adaptation Strategies Handbook. Examples of hybrid engineering. 2018.

[8] M. Browne and M. Chapman, Flower pots creating novel habitat on seawalls in Sydney Harbour. 2018.

November 27, 2018November 28, 2018

Adapting to Climate Change: Flexibility in Resilient Cities

With pressures of climate change becoming a major global issue, the idea of resilient cities has become somewhat of a buzzword. I would like to focus on one overarching theme in resilient city literature and solutions: flexibility. 100 Resilient Cities defines urban resilience as “the capacity of individuals, communities, institutions, businesses, and systems within a city to survive, adapt, and grow no matter what kinds of chronic stresses and acute shocks they experience.” This is achieved “By strengthening the underlying fabric of a city and better understanding the potential shocks and stresses it may face.”

Change is inevitable, so our cities must be able to absorb impacts, react and adapt accordingly. However, infrastructure is usually something seen as permanent and lasting (de Haan). In mechanics, one learns that brittle fracture is much more dangerous than ductile fracture. It acts as a warning of the damage to come, and can absorb more energy prior to fracture, resulting in a stronger and more resilient structure. Why not apply this at a city scale?

In general, flexibility means the possibility to introduce certain options with the assumption of changing configuration of system parameters or system components in time (Kośmieja and Pasławski). De Haan points out that “the complexity of, especially nowadays, infrastructure systems suggests that we step away from attempts to control circumstances and prepare for their consequences.” My interpretation of flexible infrastructure lies in understanding that there are different possible outcomes and acknowledging that cites (and environments) change.

Flexibility can come in different scales. For example, buildings can be designed to be more seismically sound by including literal flexible materials within them, such as timber. This can be seen in Tūranga, the new central library in Christchurch, New Zealand, designed by Schmidt Hammer Lassen of Denmark. The building includes a “seismic force-resisting system [that] is made up of a series of massive concrete walls that can rock and shift to isolate the building from peak accelerations during an earthquake.” Along with the use of pre-tensioned steel cables that stretch and flex, allowing the building to right-itself in the event of swaying, this structure is virtually earthquake-proof.

At a larger scale, the Østerbro neighbourhood of Copenhagen is a resilient neighbourhood that incorporates flexibility in rainfall systems. Due to climate change, Copenhagen has dealt with increasing levels of high-intensity rainfall that original systems could not cope with. In the creating of resilient infrastructure, these increased rainwater levels were seen as an opportunity, rather than an issue that needed to be removed. As the old rainwater management systems could not be changed (an example of the rigidity of non-resilient infrastructure), and due to minimal space restrictions, new innovations needed to be implemented locally and in tandem with increases in public green spaces. For example, in Tåsinge Plads, a square in the community, rainwater is diverted away from roofs and squares to keep the water out of sewers, while the storm water is collected in green urban areas to support the incorporation of wild urban nature in the community. In the few paved areas, ‘water parasols’ were created for children as play elements, that double as catchment basins that pump water through small channels to green spots (these are the inverted umbrella-like black structures in the image below). Here, it is important to see that flexibility is not just physical, it is a mindset – and one must bring a systems thinking approach to planning for flexibility.

One of my favourite examples of resilient infrastructure can be seen in Rotterdam. Similar water issues are being dealt with here, where water squares have been created to act as social spaces, but in the event of flooding, can also hold excess water. The flexibility in this site is clear, with multiple functions that addresses urban social living along with sustainable solutions simply, without the need for any advanced technical solutions or materials.

Urban resiliency is a buzzword for a reason: it is vital that cities address issues of our changing environments immediately, as well as do what is possible to prevent further global environmental degradation. A key component to this change is to introduce flexibility in approaching problems and at different scales. The Anthropocene is upon us, human activity is indeed the strongest geo-technical force at this moment, but why not try and make this impact a positive one?

OTHER RESOURCES

Maria Kośmieja, Jerzy Pasławski – https://doi.org/10.1016/j.proeng.2015.10.013

de Haan – https://doi.org/10.1016/j.futures.2011.06.001

http://www.rotterdamclimateinitiative.nl/documents/2015- enouder/Documenten/20121210_RAS_EN_lr_versie_4.pdf

https://www.sciencedirect.com/science/article/pii/S0016328711001352

https://link.springer.com/content/pdf/10.1007%2F978-3-319-49730-3.pdf

https://www.curbed.com/2018/5/11/17346550/organic-architecture-infrastructure-green-design

https://www.worldbank.org/en/results/2017/12/01/resilient-cities

https://openknowledge.worldbank.org/handle/10986/11986

https://www.resilientcity.org/index.cfm?id=11900

https://www.iiste.org/Journals/index.php/CER/article/viewFile/38207/39282

http://www.100resilientcities.org/resources/

November 22, 2018November 29, 2018

Reclaimed Water in Washington State

1. Why reclaimed water?

The United States has been a global leader of reclaimed water. A variety of applications from commercial use to indirect potable use are being operated by local authorities, though most of them are in the southern parts of the country such as Florida, Arizona, and California. Considering the biggest driver of most reclaimed water projects is water scarcity, the regional unbalance of the number of applications would be reasonable.

So, if you hear about the legislation of Reclaimed Water Rule in the State of Washington in 2018, it might be surprising. Actually, the state has over a quarter-century history of reclaimed water. In 1992, the Reclaimed Water Act was enacted and approximately 30 reclaimed water facilities are currently operating in the state ⁽¹⁾⁽²⁾. The purpose of the new rule is to streamline the process of permit acquisition and clarify the methods and standards ⁽³⁾.

The objectives of reclaimed water use in Washington State are various such as discharge regulations, impaired water bodies, and water supply needs. Current reclaimed water applications in Washington State include irrigation (agriculture, forest, golf course, turf, and urban landscape), urban use (street sweeping, dust suppression, and toilet flushing), and environmental use (groundwater recharge, wetlands enhancement, and stream-flow augmentation) ⁽²⁾.

2. City of Yelm

One of the local authorities utilizing reclaimed water is the City of Yelm. The initial motivation of the project was to prevent groundwater contamination caused by septic systems within the city. Because the Nisqually River, which received the discharge from the wastewater treatment plant, supported Pacific Salmon and cutthroat trout, the second treatment was not satisfactory for those fish. So, the city decided to construct the Yelm Water Reclamation Facility. Reclaimed water is produced with advanced treatment including chemical coagulation, upflow sand filters, and chlorine disinfection after the second treatment. One of the applications is to discharge it into the artificial surface and submerged wetlands which eventually recharges groundwater. In winter, excessive reclaimed water is utilized for power generation ⁽¹⁾.

In spite of the above successful story, though, the facility stopped to provide reclaimed water for six weeks in the summer of 2017 after the staff confirmed that the Total Kjeldahl Nitrogen (TKN) exceeded the reclamation water standard. The main cause of the malfunction was inadequate maintenance. Though the facility was built with state-of-the-art technology in 1999, required upgrades had not been done due to financial constraints. Furthermore, the facility had been operated by consultants, instead of experienced staff ⁽⁴⁾.

3. King County

Another applicational example is King County, which includes the City of Seattle, operating water reclamation projects since 1997 ⁽¹⁾. The main driver of reclaimed water is to enhance resiliency to drought and climate change, and a growing population ⁽¹⁾. However, King County admits the difficulty of finding enough users for reclaimed water because of their abundant water supply ⁽⁵⁾. Nevertheless, the county is keen on expanding reclaimed water projects.

The main usage of reclaimed water in King County consists of irrigation (e.g. soccer field, golf course, landscape), industry (e.g. building heating, on-site processes), and environment (wetland enhancement) ⁽⁶⁾. One of the recent projects is wetland enhancement at Chinook Bend Natural Area. The main driver of the project was to enhance native plants and control reed canary grass ⁽⁷⁾. Existing culverts, pipes, and wetland were converted to open channels and the new four-acre wetland which enhances the environment at Chinook Bend ⁽⁷⁾.

4. Conclusion

The lack of water resources, growing population, and advanced technology have contributed to the increasing numbers of water reclamation applications in the southern US. Moreover, the necessity of adaptation to the expected effects of climate change has also encouraged municipalities which are not necessarily lacking water supply to engage in water recycling. Though the country still does not have a national regulation for reclaimed water, the United States Environmental Protection Agency issued a report in 2018 which encourages local authorities suffering from water scarcity to utilize reclaimed water for potable use ⁽⁸⁾. Although there is no current movement of potable use in Washington State, it is quite intriguing that the state has been keen on expanding their applications before the expected catastrophe brought by climate change happens.

References

(1) Cupps, K. and Morris, E. Case Studied in Reclaimed Water Use: Creating new water supplies across Washington State. 2005

(2) WateReuse. WateReuse Pacific Northwest.

Pacific Northwest

(3) Schroeder Law Offices. Washington Reclaimed Water Act Adopted.

https://www.water-law.com/washington-reclaimed-water-rule-adopted/

(4) Kollar, A. Yelm Water Reclamation Facility Back Running. Nisqually Valley News. July 27, 2017

http://www.yelmonline.com/news/article_c69b0cfa-72fe-11e7-955a-0b8b1bdb5ee3.html

(5) Wastewater Treatment Division, Department of Natural Resources and Parks, King County. King County Recycled Water Program Strategic Plan 2018-2037. 2018

(6) King County. Recycled Water.

https://kingcounty.gov/services/environment/wastewater/resource-recovery/recycled-water.aspx

(7) King County. Wetland enhancement at Chinook Bend Natural Area.

https://www.kingcounty.gov/depts/dnrp/wtd/system/carnation/chinook-bend.aspx

(8) The United States Environmental Protection Agency. Mainstreaming potable water reuse in the United States: strategies for leveling the playing field. 2018

November 11, 2018December 19, 2018

Natural Capital and Ecosystem Benefits: An Overview of Metro Vancouver Water Supply & Wastewater Infrastructure Systems

Metro Vancouver water supply depends on the stock of natural capital of the Vancouver watershed. Vancouver raw water is from snowmelt and rainwater from the mountains. The raw water is of such quality that expensive preliminary treatment process similar to wastewater treatment process described later in this write up is eliminated. The availability of quality raw water for water supply is a global concern. In some countries and from the experience of the author, some cities water treatment plants have multiple unit processes of larger scale of the wastewater treatment process described in this paper due to poor quality raw water available to meet water needs. However, questions needing answers are: what is the value of the Vancouver water shed? Could it be valued at combined valuation of water supply and wastewater collection and treatment system’s performance level that return all used water to standard and quality taken from nature? Lastly the write up briefly address inter-dependency of systems in order to set the stage to appreciate systems thinking; and need to preserve our natural capital to maximize our ecosystem benefits.

Figure 1: Greater Vancouver Watershed

The Water Supply System

Vancouver watersheds are protected mountain watersheds covering an area of approximately 60,000 hectares. The system itself comprises six mountain storage lakes, five dams, two major water treatment facilities; over 520km of large diameter transmission mains, 25 storage reservoirs, 19 pump stations and 8 re-chlorination stations (McMahon J, 2018). Figure 2.Figure 2: Water supply: Sources and Distribution

Water Supply & Distribution: The regional water district department provides large scale trunk transmission and treatment systems for potable water and coordinate with member municipalities. Figure 2, The municipalities take responsibilities for the reticulation systems and consumer connections (households, commercial and industrial uses). Figure 3. Hence Metro Vancouver water services department is able provides clean, safe drinking water through its member municipalities for 2.5 million residents in the Lower Mainland (McMahon, J; 2018; (“Metro Vancouver _About Us,” n.d.).

Figure 3: The municipal dimension: Water to your home

Environmental Health & Sustainable Water Use

Wastewater Collection, Treatment & Disposal: The sewer collection include the sewer catchment areas, sewer mains, sewer pump stations and wastewater treatment plants. These facilities and systems components of the wastewater systems comprise of 530km of trunk sewer; 33 pump stations. Figure 4.

Treatment Plants: Five waste water treatment plants. Lions gate and Iona-primary treatment; while lulu, Anancis and NW Langley include secondary treatment processes (McMahon J, 2018). Figures 5. The Anancies wastewater treatment plant is the largest of the five with a 350MLD capacity; occupying 51 hectares; Design Population of 1million (Mayer, C; 2018).

Wastewater Treatment Process ( Case study: the Anancis wastewater treatment plant: Video: https://vimeo.com/217633801 -CTRL click to play video)

Figure 6 : Treatment of used waterAnancis Island Wastewater Treatment Plant (Process Diagram-Primary & Secondary Process); Source: Morales M, 2011

Industrial are pre-treated at source to acceptable standards before they are received into the treatment plant. As a case study we use the The Anancis wastewater treatment comprises of two-unit processes: primary and secondary treatment processes. The primary process comprises of receiving the wastewater from the trunk main into the treatment plant; then screening and grit removal; settling. Debris from screening and grit removal are dewatered and sent to landfill (Mayer C, 2018). The secondary unit process extended the treatment wastewater process through biological process of filtration and clarification and sludge digestion. Figure. 6 (Morales, n.d.). Through the secondary process a higher quality effluent is achieved for discharge into the river. Figure 6 is the treatment process of the Anancis plant as observed from the field tour. A retrieved online video of the Anancis wastewater treatment plant operation with our field trip facilitator Craig Mayer is embedded: Video: https://vimeo.com/217633801 -CTRL click to play video (Vancouver, 2017)

Inter-dependencies with other Urban Systems

Takeaway and Questions

Vancouver is naturally endowed with good source of water supply. Not all wastewater treatment plants in Vancouver has tertiary treatment process like the Anancis plant. Some effluent quality standards discharged remain below standard- aggregate wise, water returned is less in quality than water taken from nature. While it is natural to assume that the rest of the purification process will be taken over by nature; we should be mindful that there was no contamination of our natural water courses when we harvested it from the watershed. It is proper for Vancouver to ensure all effluent discharge is of substance and quality to that taken from nature before discharge. The interdependency of our infrastructure systems as show above also show how we are entirely dependent on nature from which it is critical to preserve our natural capital. In so doing, how do we ascribe value to benefits derived from our ecosystems? What budgetary allocation should be made for example to preserve the Vancouver watershed? What is the valuation of this natural asset? Should it be assessed as the equivalent capital cost capital cost and operation cost of wastewater supply system at current dollars or equated as size of the Vancouver economy?

REFERENCES

Drinking Water Management Plan June 2011.pdf. (n.d.). Retrieved from http://www.metrovancouver.org/services/water/WaterPublications/DWMP-2011.pdf
Mayer C, 2018: “Authors Notes from Field Trip/Tour of Anancis Wastewater Treatment Plant, June 19, 2018_ Master of Engineering Leadership (MEL) Student, UBC
McMahon J, 2018: Utility Systems – Liquid Waste and Water Metro Vancouver June 19, 2018” Field Trip Ppt Presentation (Master of Engineering Leadership (MEL) Student, UBC.
Morales, M; 2011: Wastewater Management in Metro Vancouver http://tonydorcey.ca/597/11WastewaterMetro.pdf. Retrieved 6/26/2018-10:57:52
Metro Vancouver _About Us; 2018: ) Retrieved June 29, 2018, from http://www.metrovancouver.org/about/Pages/default.aspx
Penn, Michael R; 2012: Introduction to Infrastructure: an introduction to civil and environmental engineering John Wiley & Sons Inc. 2012 ISBN 978-0-470-41191-9 (pbk)
Sewer Services: https://gis.metrovancouver.org/maps/Sewer Accessed 2018-06-27 01:00:38
Vancouver, M. (2017). Anancis Waste Water Treatment Plant Tour – Oct 2012. Retrieved from https://vimeo.com/217633801
Water for Life’ 2005-2015: International Decade for Action “Water for Life” 2005-2015. Focus Areas: The human right to water and sanitation. (n.d.). Retrieved from http://www.un.org/waterforlifedecade/human_right_to_water.shtml

END

October 11, 2018October 11, 2018

Storm Water: A problem or a resource

Urban water, specifically storm water, is often viewed as a problem to be dealt with, but as the city of Vancouver and others are looking to achieve, it has the potential to be a resource that can provide value to the community. Most storm water starts out as rain, which is clean, fresh water, but once it reaches the surface it often becomes contaminated with debris and toxins found on the ground. The traditional method for dealing with this contamination is to either send it to a water treatment facility, or in some cases, to just discharge it to a larger water body. Is there a better solution?

Some cities have taken the innovative approach to utilize this water to their advantage. Cities like Edmonton, Canada have challenged developers to utilize the water in a way that increases its value, while also limiting the water discharge rate to pre-development levels. For Edmonton, this was achieved through the development of man-made ponds and lakes which can be surrounded by “Waterfront” homes. While the ponds can manage the storm water, the developer can benefit from increased land values. These Constructed Wetlands have been previously discussed and can be seen below.

While this technique works in land rich areas such as Edmonton, in Vancouver, it is more challenging, but can be implemented on a micro scale. Water is often seen as having a calming and peaceful energy to it and as such can provide a positive community feel. By introducing small water features to a community, it can boost the atmosphere as well as provide storm water management. Features like this have been built at UBC’s Wesbrook Village.

Figure 2: Water features at UBC’s Wesbrook Village provide a calm area for students

A more subtle way to create a natural feel while managing storm water is through the use of Rain Gardens and Infiltration Swales. These water features can be added to the built environment and allow for storm water to infiltrate into the ground and be naturally filtered. They are important for controlling surface runoff and treating the water quality onsite. These features can come in a variety of sizes and be aesthetically appealing while also providing ecosystem services. These management techniques are implemented around Vancouver and are part of their Integrated Storm Water Management Plan.

Figure 3: Vancouver’s Integrated Storm Water Management Plan Infiltration Swales

Overall there are a variety of methods which can be used to turn storm water into a resource which can enhance the community and the environment. Man-made ponds, water features and infiltration swales are just some of the possibilities. As each technique can be implemented in different situations, it is important to consult and work with the community to see which the best fit for a specific area is. The 17 Water-Wise Principals by the IWA outline some of the objectives that these features help to address. By utilizing these features a community can help to regenerate the natural water body, have a water sensitive design and create a water-wise community through engaging stakeholders.

Sources:

https://vancouver.ca/files/cov/integrated-stormwater-management-vision-principles-and-actions-volume-1.pdf

http://www.discoverwesbrook.com/

https://www.edmonton.ca/city_government/environmental_stewardship/water.aspx

http://www.iwa-network.org/projects/water-wise-cities/

December 11, 2017

Vancouver Convention Centre: A Case Study

Part 1: Understanding Urban Water Systems

Why are urban water systems important?

The management of urban water systems is extremely important as water is a valuable resource that is not treated as such. Sustainable urban water system design needs to consider groundwater recharge, evapotranspiration, and runoff; these are all key in using an ecosystem approach to design.

Currently humans impact the water cycle in two main ways: creating impervious ground and polluting water. Maintaining the water cycle key affects a multitude of items such as wildlife and soil conditions, these are only a few of the reasons this topic is essential for engineers to understand.

What water systems are currently in place?

Typically, cities have a potable water system and sewer water system. Newer cities also have a storm water system while older cities have this combined with the sewer system. Many north American cities have storm/sewer water separation projects underway.

Where is there room for improvement?

New developments are often required to have a water management plan to try to mimic the existing water system. Additionally, cities many require a comparison of historical water system to post development conditions. Design techniques that are slowly becoming common practice include a grey water system for non-potable needs.

Water demand has been decreasing in north America in recent years largely due to low flow fixtures. Education regarding water as a resources and water conservation is also key. One of the areas with the largest opportunity to reduce water demand is irrigation. Current irrigation practices include a large amount of run off and new technologies exist to improve this, having new technologies improved and implemented is a large challenge. Building scale treatment is an area that is up and coming; currently technology allows efficiency at the district level which means reduction in pumping stations and piping could soon be a reality.

Part 2: Case Study – Vancouver Convention Centre

The Vancouver Convention Centre underwent extensive construction with the addition of the west building for the 2010 Olympic Winter Games. Almost 9 years later the convention centre is the world first convention centre that is certified double LEED platinum. When it opened, the convention centre was certified LEED platinum for new construction; just last month the building received its second LEED platinum certification for operation and maintenance.

One of the key design features that allows the convention centre to operate to such high standards is the sophisticated black water treatment. The “plant recycles grey and black water that goes back into [the] washrooms for toilet flushing and is used for rooftop irrigation during warmer weather.” Additionally, the convention centre has a “seawater heating and cooling system [that] takes advantage of the adjacent seawater to produce cooling for the building during warmer months and heating in cooler months.”

Compared to a baseline LEED building the convention centre uses 38% less potable water due to the treatment plant and fixture choices. Since construction the treatment plant has increased its capacity by 30%, having a smaller capacity in to start with allowed for changed to be implemented easier. Furthermore, the convention centre has an “Indoor Water Use Reduction Policy” and is actively trying to promote water reduction.

In addition to the water systems the convention centre has many other sustainable features including beehives and a green roof.

Overall seeing the encouraging media reviews about the convention centre is great for the City of Vancouver.

References:

https://www.vancouverconventioncentre.com/

http://www.pcl.com/Projects-that-Inspire/Pages/Featured-Projects/VCC-Sets-LEED-Platinum-Record.aspx

December 2, 2017

IDP: Use of Virtual Reality

The term virtual reality (VR) can be interpreted in different ways depending on the context. In the building industry it is most commonly used for computer mediated systems, environments, and experiences. In other words it is used to create 3D models of projects that are supposed to aid the design process. VR tools are still Very rarely used in practice, despite the fact that many benefits have already been identified.

Advantages

The combination of VR tools and VR immersive display systems can bring real value to the design review, the communication of the design intent, and it can increase the meeting efficiency. The use of this technology enables users to walk through a 3D model of a given project and by doing so helps to understand the aesthetics of the design because it gives the viewer a more direct feel of depth and volume of the space, which is more difficult by just looking at a static layout.

Furthermore meetings and discussions gain a new level of efficiency, because participants are more engaged and act more professional. The use of VR models brings external people up to speed to the current status easier and faster, leveling the expertise and familiarity with the design between different disciplines. This keeps participants more engaged in issues, that not necessarily regard their own discipline. This provides a holistic and diverse input, which then can spark deep questions and lead to unexpected discoveries, that otherwise might not have been detected until building turnover.

Challenges

This is not to say that VR tools do not pose difficulties or challenges. When using VR the appropriate level of detail has to be considered, as too many trivial issues might arose from a too detailed model. Similarly sometimes less is more when it comes to the modeled environment. Often intermediate designs are filled with placeholders, which will be redesigned in a later state of the process. Are those placeholders to detailed they might convey a wrong image of the design and could create a misinterpretation for those not familiar with the design process.

The preparation of VR models requires a significant amount of preparation and coordination effort, a process that usually takes up several days. By the time the model is finished the design might have already changed.

Conclusion

To sum up, VR tools give opportunities to improve the design process by increasing meetings efficiency, and helping to keep all participants engaged, so that maybe even hidden issues can be identified. But at the same time very careful planning in preparing is necessary to avoid misinterpretations due to a unfit level of detail in the model. Today Virtual Reality is still underutilized, but one can hope that as the industry develops and becomes better defined the use those tools will increase and improve the design process.

Sources:

“Virtual Reality to Support the Integrated Design Process: A Retrofit case Study”
Yifan Liu, Jennifer Lather, John Messner, 2014

November 12, 2017

The Dutch View Rising Sea Level as Opportunity, Rather Than Threat

In the Netherlands, a country that largely lies below sea level, an innovative approach to urban storm water management is not just an achievement, but a necessity. The Dutch have a unique view of their situation and choose to “live with the water, rather than struggle to defeat it.” In fact, the special relationship with water develops at a young age for those who grow up in the country, as children are thrown into the pool fully clothed to earn a swimming certificate. The fact that flooding is a major threat to the country is approached head on with a combination of Dutch ingenuity and determination.

Low Impact Design

The Dutch hold the view that traditional flood barriers and storm water management practices are not adequate to address the rising tides brought on by climate change. Their solution is to let the water in, where possible, rather than continuing to build up and against it.

“The Dutch devise lakes, garages, parks and plazas that are a boon to daily life but also double as enormous reservoirs for when the seas and rivers spill over.”

Water Plaza Rotterdam: A community space where people and water coexist

LID mimics the natural water system for collection and drainage of storm water

A keen example of this low impact design for storm water is the Water Plaza in Rotterdam, a public space that has been designed as a community hub but also features sunken infrastructure and green, pervious areas to sustainably collect rain and storm water and provide drainage.

Making Room for the River

The Dutch are using concepts of integrative water management and low impact design to redesign cities and “make room for the river.” Instead of building flood defences higher, the Dutch are actually taking on the task of removing these barriers to provide room for swelling rivers. The benefit of this is two-fold: sustainable flood management combined with generation of urban living space.

The redesigned River Waal provides room for river swells and an island with riverside park

The room for the river concept re-generates the connection between local communities and the natural water ecosystem by developing urban river parks and recreation along the rivers. Banks of the River Waal have been constructed as large gradual slopes, both increasing the floodplain and providing space for water infiltration and communities to gather along the river.

Bringing the Dutch Model to Canada

The province of Alberta, like many other regions worldwide, are excited about what the Dutch are doing to prepare for flooding. In response to the terrible floods in 2014 in Calgary, Alberta, the province has closely collaborated with Dutch water authorities to implement Room for the River integrative water management practices right here at home in Canada!

References:

“How the Dutch Make ‘Room for the River’ by Redesigning Cities.” Scientific American: https://www.scientificamerican.com/article/how-the-dutch-make-room-for-the-river/

“The Dutch Have Solutions to Rising Seas. The World is Watching.” The New York Times: https://www.nytimes.com/interactive/2017/06/15/world/europe/climate-change-rotterdam.html?_r=0

Ruimte voor de rivier website: https://www.ruimtevoorderivier.nl/english/

Alberta’s Room for the River Approach: https://albertawater.com/how-is-water-governed/what-is-room-for-the-river

Water Plaza Rotterdam: http://www.publicspace.org/en/works/h034-water-square

Images 1 & 2

Image 3

Image 4