Sustainable Implant
Encyclopedia
Sustainable implant is an urban typology
that acts as a decentralized infrastructure provision hub on the neighborhood or district scale. Sustainable implants provide integrated infrastructure services that maintain cycles of energy, water and material, as well as provides social and economic returns. The concept originates from Arjan van Timmeren’s research, Autonomy & Heteronomy (2006), as an answer to the problem of scale versus innovation
in infrastructure
; wherein infrastructure benefits from increasing returns to scale but suffer from extremely slow rate of change and turnover. To answer this problem, the sustainable implant is an instrument for mid-scale facilitation of alternative system innovation. The sustainable implant is a synthesis of techniques for sustainable processing of urban flows within an ecological processing device. The objective of a sustainable implant is to generate qualitative and quantitative improvements for utility service provision.
A sustainable implant cannot be regarded as a fixed design that can be repeated. The device comprises a guiding principle for a sustainable solution to the mainly non-sustainable flows in new or existing neighborhoods making use of E. F. Schumacher
’s appropriate technology
, matching technology to need. The sustainable implant facilitates the joint performance of the community as a cognitive agent within transition processes
into sustainable development
. On a neighborhood or district level, the Sustainable Implant entails the design of a more sustainable main structure for the transportation of water, wastewater, nutrients, energy, materials and/or waste.
The sustainable implant is matched to the social culture, the micro-climate, and the client’s ambitions. The technical morphology the Sustainable Implant is formulated by comparing relevant alternatives against the conventional approach. The maintenance of clean urban cycles (via the sustainable implant’s integrated infrastructure approach) is analyzed to prove the fulfillment of the sustainability ambition. Beyond technocracy, the Sustainable Implant is to be socially calibrated and economically profitable.
and returns to scale
in the field of infrastructure
by means of decentralization
of utility provision on an appropriate scale such that a more sustainable urban development can be achieved. In contrast to sustainable architecture
, the sustainable implant is related to the flow of materials and energy through the built environment
. A sustainable implant will often use decentralized sanitation and reuse for enhanced reuse of water, energy and nutrients, and waste.
In his research, Arjan van Timmeren formulated the following five questions:
It is of importance to recognize the need for connection or interconnection with networks at higher scale levels. In fact, the pursuit of full closure or “autarky” even counteracts the principle of the “external economies of scale”. By contrast, the arrangement of the cluster within the larger network can respond to a wish for self-sufficiency, creating some sort of a “quasi-autarky”, with as a direct advantage the use as a fall-back scenario of the increasing dependence on other areas, countries or even continents.
Such an alternative network principle can also help breaking through the historical relations between the internal organization within the organizations themselves, and the connections to each other and to the more general social structures in the specific localities.
site. The Sustainable Implant in that case featured biogassification of organic waste, community composting, and parking facilities. Programmatically and physically, the Sustainable Implant connected to a hotel and spa, which utilized the rest warmth.
----
on the periphery of Lübeck
with good public transportation access and a local primary school.
Notable elements in Flintenbreite are separation of blackwater
, greywater
, and stormwater
; vacuum sewer
and anaerobic digestion
of organic refuse; and a local integrated infrastructure provision company. The local infrastructure company provides electricity, heat, water and wastewater service from one technical building. The technical building is the hub of infrastructure provision. All of the machines are hidden in the basement and in the back of the ground level. The rest of the ground level is the community center, consisting of a large room, an alcove with a kitchenette, an outdoor patio, and bathrooms. The inhabitants have adapted the center for their needs over time.
The infrastructure is supplied to the rows of dwellings in a compact concrete connection (1.5 meters by 0.3 meters), including the hot water, hot water return, vacuum sewer (63 mm pipe diameter), drinking water, electricity, and telecom.
Impressively, Infranova GmbH is able to provide service for 20% less than conventional suppliers. This is attributed to the integration of the infrastructure provision. The economic success as well as the ecological success of the project is a positive case study for the Sustainable Implant and the Erasmusveld Energy BV.
Infranova GmbH employs one full-time caretaker who had previous experience as a hotel caretaker, so he is familiar with HVAC systems. The owner of Infranova is Ralph Otterpohl, whose company OtterWasser conceptualized the neighborhood. The inhabitants can be stakeholders in Infranova for a one-time fee of €350.00. As stakeholders, they have a vote on community issues but do not share any profits. In fact, Infranova is not run as a profit business; it simply keeps the cost of infrastructure services as low as possible. The residents profit from the more intimate relationship with their infrastructure provider. OtterWasser is called upon 2–3 times a week for conversations about the neighborhood regarding issues not related to infrastructure, such as gardening tips. Generally, inhabitants are proud of their neighborhood and the infrastructure.
The organization of Flintenbreite offers an important case study for Erasmusveld. The practical data generated in its first eight years of operation gives an indication of what can be expected if a similar system is applied in Erasmusveld. For example, the amount of blackwater in a vacuum sewer (6 liters/capita per day), concentration of nutrients in the wastewater, the energy used in operating the vacuum sewer (45 kWh/capita per year), and the socio-technical operation of a combined community center and technical building.
housed in the technical building through a local heat network
. The heat network makes a ring through the neighborhood. At each block, the local heat network passes through a heat exchanger
to warm drinking water for household use and space warming. The technical building is also an intermediary between the national electricity and gas grid and the households.
Water provision: All water consumed is drinking water from the municipality.
Wastewater: Greywater is collected in the households and brought to a constructed wetland
by free-flow pipes. The constructed wetlands are vertical-flow type built at 2 m2 per person. The effluent is cleaner than that of the municipal wastewater treatment plant. Blackwater is collected by the vacuum sewer into the technical building. The final effluent will be a liquid fertilizer which can be reuse in agricultural processes.
Solid refuse: Separated refuse and mixed refuse are handled in the manner conventional to Lubeck; namely by curb side bins collected weekly by trash truck. Organic refuse is collected within the neighborhood in a separate container and can be manually added to the anaerobic digestion process to produce additional energy.
Long-term build up from the precipitation of struvite and carbonate in the pipes has also needed to be solved by treatment with hydrochloric acid once in five years. The toilets installed are still functioning well, but are considered too noisy. However, since installation eleven years ago, Roediger has improved their technology to make quieter toilets.
The constructed wetlands for greywater purification are performing exceedingly well, even after so many years and even in the winter. Due to the warmth of the greywater, there has been no freezing in the settling tank or in the wetland itself, and it should be noted the Lubeck’s climate is quite severe.
The other decentralized infrastructure, including the gas CHP, hot water network, storm water infiltration, and community center have performed without any noted difficulties. Socially, there has been a positive response to the development, including pride over the infrastructure and adaptive use of the community center.
In conclusion, Flintenbreite is a successful case decentralized infrastructure services, notably including the vacuum sewer, which is viewed with skepticism by many. Infranova GmbH further shows the management of decentralized infrastructure can be economically sustainable and with a simple organizational structure.
Lessons learned:
----
constructed an impressive decentralized wastewater cleansing operation and glass pyramid within a city block in downtown Kolding. It is an older pilot project, so the long term consequences can be seen.
Operationally, the largest problem is odor, which is a serious nuisance to the inhabitants. The aeration pond is an open system, and continually smells like sewerage, the strength of which varies from day to day depending upon the weather.
Water provision: Besides drinking water, rainwater is harvested from building roofs. It flows down gutters into a storage tank inside the block. From there it is pumped through a simple fabric filter into the homes for toilet flushing and a washing machine. One difficulty has been slightly dirty water after a long period of no rain in which dust settles on the roofs. Then, that first rainwater is a bit darker, and almost every time complaints are made. The solution is further filtration of the rainwater before use, or education of the inhabitants that the water may be clouded. In the driest part of the year, the rainwater must be supplemented with drinking water.
Wastewater: Decentralized sanitation of wastewater is the most import element of the scheme. Blackwater and greywater are collected together inside the block by use of a normal sewer into a buffer tank. From there, the sludge is settled out, which is removed and treated in the municipal WWTP, so not all parts of the wastewater stream are treated in the neighborhood. The remaining liquid fraction of the wastewater passes through a series of reactors for aeration, clarifying, and purification with ozone and ultraviolet light. After this last step, the cleaned wastewater enters the pyramid, where it was meant for irrigation and supporting tilapia fish. However, both of these functions have ceased. Finally, after the pyramid, the wastewater is infiltrated into surface water.
Solid refuse: Inside the block, the inhabitants have drop-off facilities for mixed refuse, glass, paper, problem refuse (chemical, metal, batteries, &c), and organic refuse. The drop-off bins are housed within well designed closets for easy use with good instructions and green roofs. The municipal refuse collection company removes the refuse from bins within the closet. Organic refuse is collected in a series of 1 m3 boxes in the block. At any time, only one box is unlocked. When it is full, the next box is opened and the full box is locked. At the end of the year, all of the boxes are removed and composted to create fertilizer by the caretaker company hired for maintenance. It is a simple solution that works well except for the high level plastic bags used which pollute the refuse stream.
and now sits unused. At the base of the pyramid, there are three water ponds in a cascade which hosted tilapia fish when it was constructed, but now only support algae. According to the caretaker, the problem is three-fold: firstly, the community has changed from owners to renters, and the renters have no long-term invested interest in utilizing the space provided; second, no professional cultivator can use the greenhouse because it is too small with too many stairs; third, the pyramid is a repetition of service, because almost every apartment is equipped with its own small glass-enclosured patio in which small plants can also be grown with more convenience.
Lessons learned:
Typology (urban planning and architecture)
Typology is the taxonomic classification of characteristics commonly found in buildings and urban places, according to their association with different categories, such as intensity of development , degrees of formality, and school of thought...
that acts as a decentralized infrastructure provision hub on the neighborhood or district scale. Sustainable implants provide integrated infrastructure services that maintain cycles of energy, water and material, as well as provides social and economic returns. The concept originates from Arjan van Timmeren’s research, Autonomy & Heteronomy (2006), as an answer to the problem of scale versus innovation
Innovation
Innovation is the creation of better or more effective products, processes, technologies, or ideas that are accepted by markets, governments, and society...
in infrastructure
Infrastructure
Infrastructure is basic physical and organizational structures needed for the operation of a society or enterprise, or the services and facilities necessary for an economy to function...
; wherein infrastructure benefits from increasing returns to scale but suffer from extremely slow rate of change and turnover. To answer this problem, the sustainable implant is an instrument for mid-scale facilitation of alternative system innovation. The sustainable implant is a synthesis of techniques for sustainable processing of urban flows within an ecological processing device. The objective of a sustainable implant is to generate qualitative and quantitative improvements for utility service provision.
A sustainable implant cannot be regarded as a fixed design that can be repeated. The device comprises a guiding principle for a sustainable solution to the mainly non-sustainable flows in new or existing neighborhoods making use of E. F. Schumacher
E. F. Schumacher
Ernst Friedrich "Fritz" Schumacher was an internationally influential economic thinker, statistician and economist in Britain, serving as Chief Economic Advisor to the UK National Coal Board for two decades. His ideas became popularized in much of the English-speaking world during the 1970s...
’s appropriate technology
Appropriate technology
Appropriate technology is an ideological movement originally articulated as "intermediate technology" by the economist Dr...
, matching technology to need. The sustainable implant facilitates the joint performance of the community as a cognitive agent within transition processes
Transition Towns
Transition Towns is a grassroots network of communities that are working to build resilience in response to peak oil, climate destruction, and economic instability...
into sustainable development
Sustainable development
Sustainable development is a pattern of resource use, that aims to meet human needs while preserving the environment so that these needs can be met not only in the present, but also for generations to come...
. On a neighborhood or district level, the Sustainable Implant entails the design of a more sustainable main structure for the transportation of water, wastewater, nutrients, energy, materials and/or waste.
The sustainable implant is matched to the social culture, the micro-climate, and the client’s ambitions. The technical morphology the Sustainable Implant is formulated by comparing relevant alternatives against the conventional approach. The maintenance of clean urban cycles (via the sustainable implant’s integrated infrastructure approach) is analyzed to prove the fulfillment of the sustainability ambition. Beyond technocracy, the Sustainable Implant is to be socially calibrated and economically profitable.
Development of the sustainable implant concept
The sustainable implant originated from the desire to find harmony between autarkyAutarky
Autarky is the quality of being self-sufficient. Usually the term is applied to political states or their economic policies. Autarky exists whenever an entity can survive or continue its activities without external assistance. Autarky is not necessarily economic. For example, a military autarky...
and returns to scale
Returns to scale
In economics, returns to scale and economies of scale are related terms that describe what happens as the scale of production increases in the long run, when all input levels including physical capital usage are variable...
in the field of infrastructure
Infrastructure
Infrastructure is basic physical and organizational structures needed for the operation of a society or enterprise, or the services and facilities necessary for an economy to function...
by means of decentralization
Decentralization
__FORCETOC__Decentralization or decentralisation is the process of dispersing decision-making governance closer to the people and/or citizens. It includes the dispersal of administration or governance in sectors or areas like engineering, management science, political science, political economy,...
of utility provision on an appropriate scale such that a more sustainable urban development can be achieved. In contrast to sustainable architecture
Sustainable architecture
Sustainable architecture is a general term that describes environmentally conscious design techniques in the field of architecture. Sustainable architecture is framed by the larger discussion of sustainability and the pressing economic and political issues of our world...
, the sustainable implant is related to the flow of materials and energy through the built environment
Built environment
The term built environment refers to the human-made surroundings that provide the setting for human activity, ranging in scale from personal shelter and buildings to neighborhoods and cities that can often include their supporting infrastructure, such as water supply or energy networks.The built...
. A sustainable implant will often use decentralized sanitation and reuse for enhanced reuse of water, energy and nutrients, and waste.
In his research, Arjan van Timmeren formulated the following five questions:
- To what extent are the current technical (infra)structures decisive for the possibilities and impossibilities of sustainable development?
- Can the central or decentralized solution of the essential flows generate further processes of preservation at a higher scale level?
- Is there an optimal scale for self-sufficiency per flow, and, if there is, what is this optimal scale?
- To what extent can user participation and involvement increase by solving sustainability issues?
- Should the various techniques for the optimization of the flows be combined in one device and can this be done, or should they be integrated separately into existing (infra)structures or buildings?
It is of importance to recognize the need for connection or interconnection with networks at higher scale levels. In fact, the pursuit of full closure or “autarky” even counteracts the principle of the “external economies of scale”. By contrast, the arrangement of the cluster within the larger network can respond to a wish for self-sufficiency, creating some sort of a “quasi-autarky”, with as a direct advantage the use as a fall-back scenario of the increasing dependence on other areas, countries or even continents.
Such an alternative network principle can also help breaking through the historical relations between the internal organization within the organizations themselves, and the connections to each other and to the more general social structures in the specific localities.
Criteria for sustainable implants
There are three groups of Sustainable Implant criteria: environmental, spatial, and user-related.| Category | Criteria | Description |
|---|---|---|
| Environmental | Maintains cycles as much as possible | Maximizes the reuse of flows of material, energy and nutrients. The desired effect is to limit the amount of inputs from outside the system and reduce the amount of non-reuseable refuse exiting the system. |
| Security and consistency of supply | Infrastructure services are free from maintenance and disturbances, with back-up systems where necessary. | |
| Minimum added raw materials | Infrastructure processes use minimum chemicals and additives from outside. The construction of the physical infrastructure is wise in choice of materials. | |
| Minimum pollution of soil, air, ground area and surface water | Infrastructures and processes do not emit pollutants nor do they leak pollutants. | |
| Maximum guarantee of hygiene and safety | The Sustainable Implant is free from risks and threats to physical safety, clean and hygienic facility, and no perceived risks by society. | |
| Minimum energy use and maximum renewable energy generation | Collection, transportation and processing of Sustainable Implant components uses minimum energy while energy harvest is maximized. | |
| Resilience to sabotage/incorrect use | Systems are robust and designed for apathetic and malignant users. | |
| Future value | The Sustainable Implant has the capacity to evolve by remaining flexible in order to not become obsolete. | |
| Spatial | Optimizes collection and transport | Collection and transport of flows in the neighborhood (water, wastewater, solid refuse, &c.) is maximized regarding space, energy and material. Spatial consequences are determined by transportation techniques and clustering of processes. |
| Minimizes / optimizes use of materials | Building materials are demountable and the Sustainable Implant structure is flexible and easy to manipulate. | |
| Adaptation and extension | The Sustainable Implant can add/remove processes and expand/shrink capacity of processes. | |
| Screening off against sabotage and vandalism | The Sustainable Implant as well as the connections between the Implant and the neighborhood are impenetrable to sabotage, while remaining visible. | |
| Optimized land use | The footprint of the building is minimized. Systems dependent upon sunlight are appropriately positioned. Loading docks, access space, and nuisance zones are optimized. | |
| Fitting into the living environment | Health, safety, noise nuisance, vibrations, visual nuisance, and odor risks are eliminated such that the Sustainable Implant fits into an urban setting. | |
| Accessibility of parties involved | The Sustainable Implant is permeable by control groups, managers, maintenance staff, and educational tours. Processes are tangible from a distance while being out-of-reach by unauthorized persons. | |
| Aesthetic quality | Beauty is a criteria for a building’s lasting success. | |
| User-related | Equal or more comfort | The infrastructure and connections within homes are odor-free, robust, easy-to-use, quiet, and unimposing. |
| Similar costs | The return on investment, maintenance, and management costs of the Sustainable Implant are equal to or less than with conventional infrastructure, inclusive of costs related to developing buildings connected to the Sustainable Implant. | |
| Equal or greater ease of use | Users must be confronted with an equally easy or easier specific use of their home installations as well as maintenance rituals. | |
| Independence of specialized institutions and obligatory networks | The users are shareholders in the Sustainable Implant and independent of larger cooperations which they cannot control, thus inhabitants have personal development possibilities and a hand in their own futures. | |
| Image and transparency | Sense-ability, monitoring, feedback, and visual recognition of the Sustainable Implant and the processes are maximized; this leads to a rational and efficient use of resources and enhances the joyousness and usability of otherwise invisible infrastructure. |
EVA Lanxmeer
A Sustainable Implant was designed (but not yet realized) for the EVA LanxmeerEVA Lanxmeer
EVA lanxmeer is the name of a éco-quartier build from 1994 to 2009 in the Dutch town of Culemborg in Nederland.It is an environmentally-friendly-housing development....
site. The Sustainable Implant in that case featured biogassification of organic waste, community composting, and parking facilities. Programmatically and physically, the Sustainable Implant connected to a hotel and spa, which utilized the rest warmth.
----
Flintenbreite, Lubeck
The Flintenbreite neighborhood is a market-driven project emphasizing innovative infrastructure services for energy efficiency. In 1999, a portion of the dwellings (for 111 inhabitants) and a technical building with a community center were constructed. Eleven years later, the remaining planned buildings for a total of 350 inhabitants have still not been built due to the poor housing market. The site is on a greenfieldGreenfield land
Greenfield land is a term used to describe undeveloped land in a city or rural area either used for agriculture, landscape design, or left to naturally evolve...
on the periphery of Lübeck
Lübeck
The Hanseatic City of Lübeck is the second-largest city in Schleswig-Holstein, in northern Germany, and one of the major ports of Germany. It was for several centuries the "capital" of the Hanseatic League and, because of its Brick Gothic architectural heritage, is listed by UNESCO as a World...
with good public transportation access and a local primary school.
Notable elements in Flintenbreite are separation of blackwater
Blackwater (waste)
Blackwater is a term dating to at least the 1970s used to describe wastewater containing fecal matter and urine. It is also known as brown water, foul water, or sewage...
, greywater
Greywater
Greywater is wastewater generated from domestic activities such as laundry, dishwashing, and bathing, which can be recycled on-site for uses such as landscape irrigation and constructed wetlands...
, and stormwater
Stormwater
Stormwater is water that originates during precipitation events. It may also be used to apply to water that originates with snowmelt that enters the stormwater system...
; vacuum sewer
Vacuum sewer
A vacuum sewer system uses the differential pressure between atmospheric pressure and a partial vacuum maintained in the piping network and vacuum station collection vessel. This differential pressure allows a central vacuum station to collect the wastewater of several thousand individual homes,...
and anaerobic digestion
Anaerobic digestion
Anaerobic digestion is a series of processes in which microorganisms break down biodegradable material in the absence of oxygen. It is used for industrial or domestic purposes to manage waste and/or to release energy....
of organic refuse; and a local integrated infrastructure provision company. The local infrastructure company provides electricity, heat, water and wastewater service from one technical building. The technical building is the hub of infrastructure provision. All of the machines are hidden in the basement and in the back of the ground level. The rest of the ground level is the community center, consisting of a large room, an alcove with a kitchenette, an outdoor patio, and bathrooms. The inhabitants have adapted the center for their needs over time.
The infrastructure is supplied to the rows of dwellings in a compact concrete connection (1.5 meters by 0.3 meters), including the hot water, hot water return, vacuum sewer (63 mm pipe diameter), drinking water, electricity, and telecom.
Construction and operation
The investment for neighborhood infrastructure and the technical building with a community space was made by the integrated infrastructure provider, the independent company Infranova GmbH & Co KG. The building construction was done by one developer (Schutt) and the vacuum system was built by Roediger Vacuum GmbH, who also supplied the vacuum toilets. The neighborhood was built without any government subsidies, expect for a planning subsidy given to OtterWasser GmbH for designing the separated water system. The homes are available at market price, and may even be slightly lower than market price, given the amount of green space surrounding and location adjacent to a primary school.Impressively, Infranova GmbH is able to provide service for 20% less than conventional suppliers. This is attributed to the integration of the infrastructure provision. The economic success as well as the ecological success of the project is a positive case study for the Sustainable Implant and the Erasmusveld Energy BV.
Infranova GmbH employs one full-time caretaker who had previous experience as a hotel caretaker, so he is familiar with HVAC systems. The owner of Infranova is Ralph Otterpohl, whose company OtterWasser conceptualized the neighborhood. The inhabitants can be stakeholders in Infranova for a one-time fee of €350.00. As stakeholders, they have a vote on community issues but do not share any profits. In fact, Infranova is not run as a profit business; it simply keeps the cost of infrastructure services as low as possible. The residents profit from the more intimate relationship with their infrastructure provider. OtterWasser is called upon 2–3 times a week for conversations about the neighborhood regarding issues not related to infrastructure, such as gardening tips. Generally, inhabitants are proud of their neighborhood and the infrastructure.
The organization of Flintenbreite offers an important case study for Erasmusveld. The practical data generated in its first eight years of operation gives an indication of what can be expected if a similar system is applied in Erasmusveld. For example, the amount of blackwater in a vacuum sewer (6 liters/capita per day), concentration of nutrients in the wastewater, the energy used in operating the vacuum sewer (45 kWh/capita per year), and the socio-technical operation of a combined community center and technical building.
Infrastructure services
Energy: Households are supplied with warmth from natural gas cogeneration turbineCogeneration
Cogeneration is the use of a heat engine or a power station to simultaneously generate both electricity and useful heat....
housed in the technical building through a local heat network
District heating
District heating is a system for distributing heat generated in a centralized location for residential and commercial heating requirements such as space heating and water heating...
. The heat network makes a ring through the neighborhood. At each block, the local heat network passes through a heat exchanger
Heat exchanger
A heat exchanger is a piece of equipment built for efficient heat transfer from one medium to another. The media may be separated by a solid wall, so that they never mix, or they may be in direct contact...
to warm drinking water for household use and space warming. The technical building is also an intermediary between the national electricity and gas grid and the households.
Water provision: All water consumed is drinking water from the municipality.
Wastewater: Greywater is collected in the households and brought to a constructed wetland
Constructed wetland
A constructed wetland or wetpark is an artificial wetland, marsh or swamp created as a new or restored habitat for native and migratory wildlife, for anthropogenic discharge such as wastewater, stormwater runoff, or sewage treatment, for land reclamation after mining, refineries, or other...
by free-flow pipes. The constructed wetlands are vertical-flow type built at 2 m2 per person. The effluent is cleaner than that of the municipal wastewater treatment plant. Blackwater is collected by the vacuum sewer into the technical building. The final effluent will be a liquid fertilizer which can be reuse in agricultural processes.
Solid refuse: Separated refuse and mixed refuse are handled in the manner conventional to Lubeck; namely by curb side bins collected weekly by trash truck. Organic refuse is collected within the neighborhood in a separate container and can be manually added to the anaerobic digestion process to produce additional energy.
Long-term issues
Minor problems have occurred with the vacuum sewer. In the first two months there was an adjustment period for inhabitants’ behavior. After this period, errors continued to be caused by clogging of the vacuum valve by inappropriate refuse in the toilet. OtterWasser has suggested that this problem could be solved by repetition of information to the inhabitants.Long-term build up from the precipitation of struvite and carbonate in the pipes has also needed to be solved by treatment with hydrochloric acid once in five years. The toilets installed are still functioning well, but are considered too noisy. However, since installation eleven years ago, Roediger has improved their technology to make quieter toilets.
The constructed wetlands for greywater purification are performing exceedingly well, even after so many years and even in the winter. Due to the warmth of the greywater, there has been no freezing in the settling tank or in the wetland itself, and it should be noted the Lubeck’s climate is quite severe.
The other decentralized infrastructure, including the gas CHP, hot water network, storm water infiltration, and community center have performed without any noted difficulties. Socially, there has been a positive response to the development, including pride over the infrastructure and adaptive use of the community center.
In conclusion, Flintenbreite is a successful case decentralized infrastructure services, notably including the vacuum sewer, which is viewed with skepticism by many. Infranova GmbH further shows the management of decentralized infrastructure can be economically sustainable and with a simple organizational structure.
Lessons learned:
- A local integrated infrastructure provider can be economically sustainable.
- A vacuum sewer can be successful in a neighborhood, though small technical problems can be expected during the adjustment period.
- Constructed wetlands are a practically proven robust and effective method of treating greywater in a Northern European context.
- Market parties can also be drivers for decentralized infrastructure communities.
- Decentralized infrastructure and a community center are socially sustainable.
----
Kolding Wastewater Pyramid
As part of an urban renewal project in 1995, the City of KoldingKolding
Kolding is a Danish seaport located at the head of Kolding Fjord in Region of Southern Denmark . It is the site of the council Kolding Municipality. It is a transportation, commercial, and manufacturing centre, and has numerous industrial companies, principally geared towards shipbuilding...
constructed an impressive decentralized wastewater cleansing operation and glass pyramid within a city block in downtown Kolding. It is an older pilot project, so the long term consequences can be seen.
Construction and operation
The pyramid and surround infrastructure was built by the City of Kolding as a pilot project. Once finished, it was given to the inhabitants of the block as a gift. The residents continue to use the pyramid to purify their wastewater, but all other functions it was planned to serve has ceased. Of the 120 homes it serves, only 30 are occupied by their owners, and the rest are rented. The organization of owners bills for wastewater treatment the same as the municipal wastewater treatment plant would. In fact, the pyramid purifies water for less money than the WWTP. The regular maintenance for wastewater treatment is performed by a landscaping company who also looks after the green space within the block. Once a week, a staff member checks all of the gauges to make sure the system is working properly. Once a year, all of the pumps are maintained by a technical company. In the event of a problem, the landscaping company is alarmed and comes to fix it. In the case of damages to the system, such a broken pump or broken window, the organization of owners pays for replacement.Operationally, the largest problem is odor, which is a serious nuisance to the inhabitants. The aeration pond is an open system, and continually smells like sewerage, the strength of which varies from day to day depending upon the weather.
Infrastructure services
Energy: To support the decentralized wastewater system, a bank of solar PV panels were installed above a parking area. However, it does not provide enough energy to compensate for the entire operation.Water provision: Besides drinking water, rainwater is harvested from building roofs. It flows down gutters into a storage tank inside the block. From there it is pumped through a simple fabric filter into the homes for toilet flushing and a washing machine. One difficulty has been slightly dirty water after a long period of no rain in which dust settles on the roofs. Then, that first rainwater is a bit darker, and almost every time complaints are made. The solution is further filtration of the rainwater before use, or education of the inhabitants that the water may be clouded. In the driest part of the year, the rainwater must be supplemented with drinking water.
Wastewater: Decentralized sanitation of wastewater is the most import element of the scheme. Blackwater and greywater are collected together inside the block by use of a normal sewer into a buffer tank. From there, the sludge is settled out, which is removed and treated in the municipal WWTP, so not all parts of the wastewater stream are treated in the neighborhood. The remaining liquid fraction of the wastewater passes through a series of reactors for aeration, clarifying, and purification with ozone and ultraviolet light. After this last step, the cleaned wastewater enters the pyramid, where it was meant for irrigation and supporting tilapia fish. However, both of these functions have ceased. Finally, after the pyramid, the wastewater is infiltrated into surface water.
Solid refuse: Inside the block, the inhabitants have drop-off facilities for mixed refuse, glass, paper, problem refuse (chemical, metal, batteries, &c), and organic refuse. The drop-off bins are housed within well designed closets for easy use with good instructions and green roofs. The municipal refuse collection company removes the refuse from bins within the closet. Organic refuse is collected in a series of 1 m3 boxes in the block. At any time, only one box is unlocked. When it is full, the next box is opened and the full box is locked. At the end of the year, all of the boxes are removed and composted to create fertilizer by the caretaker company hired for maintenance. It is a simple solution that works well except for the high level plastic bags used which pollute the refuse stream.
Long-term issues
The pyramid continues to perform its main function of water purification, however, it is very noticeable that the inhabitants have lost interest in the pyramid. Four levels in the pyramid were planned as greenhouse space for the inhabitants; now it is only partially used by one hobbyist gardener (at no cost), while most of the greenhouse beds sit empty. This can also be seen beside the pyramid, where a piece of land was set aside for urban agricultureUrban agriculture
Urban agriculture is the practice of cultivating, processing and distributing food in, or around, a village, town or city. Urban agriculture in addition can also involve animal husbandry, aquaculture, agro-forestry and horticulture...
and now sits unused. At the base of the pyramid, there are three water ponds in a cascade which hosted tilapia fish when it was constructed, but now only support algae. According to the caretaker, the problem is three-fold: firstly, the community has changed from owners to renters, and the renters have no long-term invested interest in utilizing the space provided; second, no professional cultivator can use the greenhouse because it is too small with too many stairs; third, the pyramid is a repetition of service, because almost every apartment is equipped with its own small glass-enclosured patio in which small plants can also be grown with more convenience.
Lessons learned:
- Decentralized purification of wastewater can be provided at a lower cost than with municipal WWTP.
- The operational efficiency in wastewater treatment is influenced by the spatial arrangement of tanks to reduce the number of pumps (and electricity) used.
- Provision of rainwater on the block scale is feasible with few problems in the long-term.
- If a greenhouse is built, long-term participation by inhabitants cannot be guaranteed, so it is preferable that the space is interesting for a professional gardener or cafe or other party.
- Wastewater treatment in an urban setting must be performed in a closed container to prevent odor problems.