Dear all

A new open source paper  from my PhD is out:
Comparative analysis of sanitation systems for resource recovery: Influence of configurations and single technology components
https://doi.org/10.1016/j.watres.2020.116281

The paper comes with a data package compiling international literature and expert information on 41 technologies, their appropriateness profiles for different context, and transfer coefficients for phosphorus, nitrogen, total solids, and water. This package can be directly accessed here: https://opendata.eawag.ch/dataset/sanitation-technology-library
Please come back to me with your feedback and questions!

Abstract
Resource recovery and emissions from sanitation systems are critical sustainability indicators for strategic urban sanitation planning. In this context, sanitation systems are the most often structured using technology-driven templates rather than performance-based sustainability indicators. In this work, we answer two questions: Firstly, can we estimate generic resource recovery and loss potentials and their uncertainties for a diverse and large set of sanitation systems? And secondly, can we identify technological aspects of sanitation systems that indicate a better overall resource recovery performance? The aim is to obtain information that can be used as an input into any strategic planning process and to help shape technology development and system design for resource recovery in the future. Starting from 41 technologies, which include novel and conventional options, we build 101,548 valid sanitation system configurations. For each system configuration we quantify phosphorus, nitrogen, total solids, and water flows and use that to calculate recovery potentials and losses to the environment, i.e. the soil, air, or surface water. The four substances cover different properties and serve as a proxy for nutrient, organics, energy, and water resources. For modelling the flows ex-ante, we use a novel approach to consider a large range of international literature and expert data considering uncertainties. Thus all results are generic and can therefore be used as input into any strategic planning process or to help guide future technology development. A detailed analysis of the results allows us to identify factors that influence recovery and losses. These factors include the type of source, the length of systems, and the level of containment in storage and treatment. The factors influencing recovery are related to interactions of different technologies in a system which shows the relevance of a modelling approach that allows to look at all possible system configurations systematically. Based on our analysis, we developed five recommendations for the optimization of resource recovery: (i) prioritize short systems that close the loop at the lowest possible level; (ii) separate waste streams as much as possible, because this allows for higher recovery potentials; (iii) use storage and treatment technologies that contain the products as much as possible, avoid leaching technologies (e.g. single pits) and technologies with high risk of volatilization (e.g. drying beds); (iv) design sinks to optimise recovery and avoid disposal sinks; and (v) combine various reuse options for different side streams (e.g. urine diversion systems that combine reuse of urine and production of biofuel from faeces).

Dear all

We (me, my colleagues from 500B Nepal, Arba Minch Ethiopia, and Eawag Switzerland) finally managed to get out the results of the method we developped during my PhD, it is available here :
Developing sanitation planning options: A tool for systematic consideration of novel technologies and systems
Dorothee Spuhler, Verena Germann, Kinfe Kassa, Atekelt Abebe Ketema, Anjali Manandhar Sherpa, Mingma Gyalzen Scherpa, Max Maurer, Christoph Lüthi, Günter Langergraber

The approach enables the prioritisation of appropriate and  resource efficient sanitation technologies and systems in strategic planning . It contributes to a more citywide inclusive approach by bridging strategic citywide objectives with an area-based appropriateness assessment.

Abstract
To provide access to sustainable sanitation for the entire world population, novel technologies and systems have been developed. These options are often independent of sewers, water, and energy and therefore promise to be more appropriate for fast-growing urban areas. They also allow for resource recovery and and are adaptable to changing environmental and demographic conditions what makes them more sustainable.
More options, however, also enhance planning complexity. Structured decision making (SDM) can help balance opposing interests. Yet, most of the current research focuses on the selection of a preferred option, assuming that a set of appropriate options is available. There is a lack of reproducible methods for the identification of sanitation system planning options that can consider the growing number of available technology and the many possible system configurations. Additionally, there is a lack of data, particularly for novel options, to evaluate the various sustainability criteria for sanitation.To overcome this limitation, we present a novel software supported approach: the SANitation sysTem Alternative GeneratOr (Santiago).
To be optimally effective, Santiago is required to be integrated into an SDM approach. In this paper, we present all the elements that such anintegration requires and illustrate these methods at the case of Arba Minch, a fast growing town in Ethiopia. Based on this example and experiences from other cases, we discuss the lessons learnt and present the advantages potentially brought by Santiago for sanitation planning The integration requires four elements: a set of technologies to be looked at, decision objectives for sustainable sanitation, screening criteria to evalute technology appropriateness, and about the technologies and the casea. The main output is a set of sanitation system options that is locally appropriate, diverse in order to reveal trade-offs, and of a manageable size. To support the definition of decision objectives, we developed a generic objective hierarchy for sustainable sanitation. Because one of the main challenges lies in the quantification of screening criteria, we established the data for 27 criteria and 41 technologies in a library.The case studies showed, that if the integration is successful, then Santiago can provide substantial benefits: (i) it is systematic and reproducible; (ii) it opens up the decision space with novel and potentially more appropriate solutions; (iii) it makes international data accessible for more empirical decision making; (iv) it enables decisions based on strategic objectives in line with the sustainable development goals; (v) it allows to prioritise appropriate and resource efficient systems right from the beginning (vi) and it contributes to a more citywide inclusive approach by bridging strategic objectives with an area-based appropriateness assessment.
The here presented approach enables the prioritisation of appropriate and resource efficient sanitation technologies and systems in strategic planning. Thereby this approach contributes to SDG 6.2, 6.3, and 11, sustainable sanitation for all.

Hi Elisabeth

Thanks for the further questions!

I do not have a link where all the novel technologies are listed as I am yet in the progress of preparing a easily accessible user interface for the tool. I could share the link to a few publications where one or the other technology was included in the case study. But I hope soon the publication process on my current technology database will be done and then I will definitively share the link.
However, important is not the list of the technologies that are included, but that I am to produce a online version of the Compendium where novel options can be more easily added. From a methodological point of view, this means that the generic definitions and attributes used by the new Compendium are flexible and can be defined by the user. AND, that is what I mentioned in my previous thread: the uncertainty regarding those data especially for novel technologies can be considered. From a practical point of view, I still need to sort out how exactely to tag novel technologies to distinguish them from the others from the Compendium (you may remember that the Compendium facthsheets went through a very long and intensive reviewing process with a broad sounding board… not sure if this will be possible for each new technology added).
To be more specific:

• For the technology appropriateness assessment I consider the uncertainty of the the different attributes (e.g. water requirements) using probability functions. However, the overall technology score is a number between 0 and 100% (without standard deviation) expressing the confidence we have in the technology to be appropriate.
• For the mass flow quantification I consider the uncertainties related to the transfer coefficients resulting in a standard deviation for the quantified resource recovery and losses potentials (phosphorus, nitrogen, total solids, water). This is particularly important for novel technologies, but also for conventional technologies, transfer coefficients ARE uncertain (imagine the variability you have of the fraction of phosphorus entering the sludge and the effluent in a septic tank….). To quantify the uncertainty, I used the variability of data from different literature resources, the technology readiness level (TRL), and the confidence in the substance (e.g. phosphorus being conservative and nitrogen not).
• My cost module is really only a prototype and I paused working on it as I want to see what comes out of the World Bank costing tool and other initiatives e.g. lead by Leeds. I used cost functions of the CLARA tool and previous Eawag work and only considered uncertainty (better said “variability” ) regarding the number of users per unit (e.g. do you have one, two, or three, FSM treatment plants within a settlement).
• Aurin production: this is the process currently implemented by VUNA mainly here in Switzerland and surroundings – check it out (it is now also allowed for edible crops !!!): www.vuna.ch/aurin/index_en.html .

I also would like to specifically react on this:

“I think it's been a shortcoming for a long time that novel options are not included in many decision-making processes. On the other hand, I can also understand why that might be so. It's about risk of failure and who would be willing to shoulder the risks of implementing a little-known technology on a larger scale...”

You already state one answer to the problem, often provided by decision analysis theory: by quantifying the risk associated to different performance indicators used to compare options, we can consider this risk and thus also compare options with very different risks in the decision-making process! It is then to the decision-makers providing a value function describing how risk adverse he is…
Considering various uncertainties is one attempt to do this and the models I developed are the first step to consider novel options alongside with conventional ones. It provides however not the final solutions, but a set of options to be further evaluated regarding different criteria, maybe weighted differently by different stakeholders. One or several risk proxies as part of the criteria would allow to consider the fear of decision-makers of failure of novel technologies (and quantifying those systematically may reveals that given the local environmental factors, the actual risk of novel options are not higher than for conventional ones: e.g. imagine a very robust but strongly water dependent technology compared to a highly novel waterless option in a water scarce area…).

I am extremely happy that we have this discussion, Elisabeth! I think these aspects have not been enough discussed on the forum although they are so crucial to bring the many innovations into practice!

Kind regards,
Dorothee

Thanks a lot for your detailed reply, Dorothee. (and I have merged the two threads now)

Could you please expand a bit more on this:

The novel technologies include vermi-composting, aurin production, biochar production, etc. Different technologies have different uncertainties either because of lack of experiences or the huge diversity in design specifications. I offer a way of comparing technology appropriateness and quantifying mass flows which can take this into account.

?

Could you provide a link to the page where ALL the "novel" technologies are listed (i.e. all those that were not in the EAWAG eCompendium). I don't know aurin production or was that a typo? And could you explain how you factor in those uncertainties, also for your cost equations.

I think it's been a shortcoming for a long time that novel options are not included in many decision making processes. On the other hand, I can also understand why that might be so. It's about risk of failure and who would be willing to shoulder the risks of implementing a little known technology on a larger scale...

Regards,
Elisabeth

Dear all

Thank you, Elisabeth, for your post . To answer your questions very briefly: yes, yes, and yes…
Yes, it is the continuation of my PhD work and aims to put it into practice.
Yes, I also sometimes think the same thing: not yet another tool… but this is really not the intention!
The aim is to bring the Compendium to a next level and equip it with additional functions:

1. Systematic assessment of the technology APPROPRIATENESS IN A GIVEN CASE considering novel technologies and thus the uncertainties related to those and the local conditions
2. Generate possible and VALID SYSTEM CONFIGURATION from a set of appropriate technologies.
3. Identify SYSTEMATICALLY a set of system option as INPUT INTO STRATEGIC PLANNING (e.g. CLUES, Sanitation21, CWIS, etc.)
4. And optionally quantify resource recovery potentials and losses to soil, water, air (phosphorus, nitrogen, total solids, water)

SANTIAGO includes the mathematical models and database extending the Compendium information with systematic characterization of technologies and novel technologies. The appropriateness criteria include data on e.g. temperature, access, slope, operation and maintenance, etc.). The novel technologies include vermi-composting, aurin production, biochar production, etc. Different technologies have different uncertainties either because of lack of experiences or the huge diversity in design specifications. I offer a way of comparing technology appropriateness and quantifying mass flows which can take this into account.
My current project aims at bringing the elements from SANTIAGO online in a new eCompendium integrating the features mentioned above. This eCompendium can then be used as a decision-making support tool, as a training and capacity development tool, but also to test out the scope of new technology innovation (e.g. technology innovation XY would lead to what kind of possible system configurations… OR to make technology ZW appropriate for developing urban areas, what features need to be improved…, etc..). It should be targeted to consultants (e.g. for ADB or the World Bank), planners, policy makers, development agencies, academia, and training institutions.

Yes, it can also be a sort of a meta tool (as the compendium) bringing in the system approach into other tools such as the FSM toolbox, the World Bank Costing tool, the online version of the Compendium for Emergencies, Sampson, etc. For instance, all these tools require that technologies are assembled into entire and valid system chains. So far, this needs to be done manually depending on the knowledge and expertise of the expert, limiting the diversity of the system options to a few well known only. This could be systematized which would also allow to deal with very large numbers also and opening up the option space for novel options, which are potentially more appropriate and sustainable.

I am currently applying for different funding sources and in contact with different related tool to sketch out the integration (e.g. FSM toolbox, SSWM toolbox, CSTEP planning tool, Compendium for Emergencies, etc.). I also aim to have an eCompendium version that could be co-hosted by several relevant websites, including the SuSanA website, Eawag website, and the SSWM toolbox website.

In summary:

• SANTIAGO is a meta tool providing advanced functionalities as a complement to the Compendium
• The aim is a eCompendium3.0: an online open source user interface for capacity development and training, planning/decision-making support, and scoping of new technologies.
• The functionalities could also be integrated in other tools (e.g. generating system configurations in the FSM toolbox.
• It is by no means intended to replace the technical know-how required for detailed planning and implementation but serves to help integrate the growing number of decision criteria and technological options into the decision-making process.

And yes: I think it makes sense to merge the two threads. (edit on 24 Sept: done)
Did I answer all your question?
By the way, I also presented some more practical conclusions from the case study from Nepal at WEDC last year and I am also working of extending SANTIAGO for cost estimations – two short papers attached.

Cheers, Dorothee

Hi Dorothee,

I want to give your post a boost by putting it back on top as it looks really interesting! Is this a continuation of your PhD work? Putting your PhD work into practice? (you had earlier written about it here, should we perhaps combine the threads?: forum.susana.org/wastewater-characterisa...-of-an-urban-setting ) (edit on 24 Sept: merger now done)

When I first looked at it I thought, "not another tool..." But maybe this will be the tool of all tools? How do you see it fit with the FSM toolbox that you mentioned, would that somehow be a subset of your tool? E.g. would all the technologies for faecal sludge treatment that are in the FMS tookbox be included in your selection tool? SANTIAGO is a pretty cool name by the way, easy to remember (SANitation sysTem Alternative GeneratOr).

I think one difficult area will always be how do you compare the better known technologies with the lesser known technologies side by side? I think in practice many decision makers will naturally gravitate towards technologies that have been around for longer and shy away from those that are less well established.

For example think of vermifiltration for wastewater treatment which Hajo and Dean (and a few others) have been discussing here: forum.susana.org/205-vermifilters-or-ver...-produce-clean-water

It might have merit and potential (I can't judge it myself) but it will be hard for it to be taken seriously because of the small number of well documented implementations at a larger scale so far. How will it therefore be included (or not) in your SANTIAGO tool?

Other lesser known technologies where the same question applies could be container-based sanitation, vermifilters for blackwater treatment (worm toilets), some of those new technologies coming out the BMGF toilet grants (although they are presumably all still at an early stage and therefore NOT included in your tool (?))

Also you wrote here :

I am also in discussion with Manfred ( forum.susana.org/wastewater-characterisa...lable-sampsons#27548 ) to integrate some of these models in their new software.

Is that progressing?

And I am a little bit confused: is SANTIAGO more of a mathematical modelling thing (which is the sub-category where you had posted about your PhD thesis) or more of a planning toolkit thing (which is where this thread is now)?

Regards,
Elisabeth

Dear all

As the number of potential sanitation technologies grows, it becomes increasingly complex to combine those into appropriate and sustainable systems. How compatible are different technologies? How to ensure that all waste streams are treated? How to systematically evaluate the appropriateness of a system for a given urban setting? Such questions become more relevant than ever.
We are currently in the process of developing a new open-source online tool that enables engineers in considering systematically the growing number of new sanitation technologies and systems when choosing among options. The tool is designed to integrate in a facilitated participatory strategic planning process (following a structured decision-making approach such as CLUES) and provides a diverse set of sanitation system options, all appropriate for the case at hand. A library of over 50 technologies makes data from international literature and expert knowledge (e.g. energy requirements, access requirements) available to the local actors. The library can easily be extended in order to capture future innovations.

Please find enclosed a short factsheet about it. So far, we have tested the tool in two cases in Nepal, two studies in Ethiopia, and one in Peru.

As we are now preparing to make this tool available online, we are looking for your feedback and future testers (you can find my email address in the orange box at the end of the factsheet.
We also would like to have the feedback on two questions from the SuSanA crowd:
- Do we need such a tool?
- And where should it be hosted, respectively, how should it be accessed (e.g. FSM toolbox, SuSanA homepage, SSWM Toolbox, etc.)?

THANK YOUR FOR YOUR SUPPORT!
Dorothee

Dear Carol

Thank you for your interest.
You pinpoint a very important message of the paper: the process of selecting the "right" sanitation technology options is very complex and cannot be oversimplified.
You also mention a other important aspect: legal criteria, environmental conditions, flexibility, etc can be used to narrow down the option space. However, it is not alway so clear how "fixed" these factors are: maybe these laws could be changed in order to allow for a technology or sanitation system options which has many advantages regarding many other criteria!?! (We have seen this example here in Switzerland for the procedure used by the VUNA team, a Eawag spin-off producing liquid fertilizer from urine).

I do not have a ready made example from an industrialized country but what I can say from the research which I have done with this model so far is that it remains always somehow complex and a fancy model will not do the job alone! It has to be part of a collaborative, structured, and facilitated planning process following the framework of e.g. CLUES.

I see two main added values of models like mine:

• The process of pre-selection is systematized and therefore made reproducible and more transparent (also stakeholders can be involved in defining and quantifying pre-selection criteria as mentioned above).
• The process of system generation is automatized and therefore allows to consider a very large and divers number of different technological concepts.

The output is not the "one single best option" but a divers and locally appropriate set of sanitation system options that is still of manageable size and can support the discussions and the decision-making process among stakeholders and decision makers.

Cheers, Dorothee

Dorothee,

Your recent paper made available free is cool! Very sobering that for one place in Nepal you assessed the appropriateness of 40 technologies and generated 17,955 appropriate system options. Ah ha! That shows how complex all this is and the need for tools like the ones you offer.

Do you have examples from industrialized countries, where options are fewer? Many rural and suburban areas of the US are confronted with failing onsite septic systems and the inability of cities to maintain or replace sewers is also well documented. I see the options as far fewer owing to a rigid regulatory environment, escalating costs to individual homeowners and local governments, the difficulty of getting the policy discussion underway when a way forward seems lacking.

Any suggestions?

Here are a couple of overviews of the situation in the US problems that are helpful to generalists advocates :

• America's Failing Septic Threat. Brett Walton. Circle of Blue. 2015. www.circleofblue.org/2015/world/alabama-clean-water-polluti/
• 2017 Infrastructure Report Card - Wastewater. American Society of Civil Engineers. www.infrastructurereportcard.org/cat-item/wastewater/

Thank you for your work,

Carol

Dear all
The publication I mentioned in my previous post "Generation of sanitation system options for urban planning considering novel technologies" can be accessed freely for the next month:
authors.elsevier.com/a/1XbyY9pi-IGzp

Cheers, Dorothee

Generation of sanitation system options for urban planning considering novel technologies.
Spuhler D., Scheidegger A., Maurer M.
The identification of appropriate sanitation systems is particularly challenging in developing urban areas where local needs are not met by conventional solutions. While structured decision-making frameworks such as Community-Led Urban Environmental Sanitation (CLUES) can help facilitate this process, they require a set of sanitation system options as input. Given the large number of possible combinations of sanitation technologies, the generation of a good set of sanitation system options is far from trivial. This paper presents a procedure for generating a set of locally appropriate sanitation system options, which can then be used in a structured decision-making process. The systematic and partly automated procedure was designed (i) to enhance the reproducibility of option generation; (ii) to consider all types of conventional and novel technologies; (iii) to provide a set of sanitation systems that is technologically diverse; and (iv) to formally account for uncertainties linked to technology specifications and local conditions. We applied the procedure to an emerging small town in Nepal. We assessed the appropriateness of 40 technologies and generated 17,955 appropriate system options. These were classified into 16 system templates including on-site, urine-diverting, biogas, and blackwater templates. From these, a subset of 36 most appropriate sanitation system options were selected, which included both conventional and novel options. We performed a sensitivity analysis to evaluate the impact of different elements on the diversity and appropriateness of the set of selected sanitation system options. We found that the use of system templates is most important, followed by the use of a weighted multiplicative aggregation function to quantify local appropriateness. We also show that the optimal size of the set of selected sanitation system options is equal to or slightly greater than the number of system templates. As novel technologies are developed and added to the already large portfolio of technology options, the procedure presented in this work may become an essential tool for generating and exploring appropriate sanitation system options.

Hi Kris,

All the modesl are open-source.
The model that generates all possible sanitation system options from a set of potential novel and conventional sanitation and the model technologies (SanitationSystemBuilder) and the model that quantifies the appropriateness of the technology and system options (and corresponding system options) in a given setting considering uncertainty based on a set of locally identified "appropriateness attributes" (TechAppA) are also out there on github: github.com/Eawag-SWW
The first is written in Julia, but can be used by any kind of open-source editor on windows, linus or osx (e.g. I use Atom).
The second one is written in R and can be used e.g. with RStudio.

The corresponding publication to cite is here: doi.org/10.1016/j.watres.2018.08.021
There is also a presentation from the WEDC conference but not sure if the slides as stand alone are very useful: www.dropbox.com/s/sfhf9sgluipclra/201807...ction_final.pdf?dl=0

As mentioned earlier, there is not user interface and therefor the usage is not user friendly at all. In case you intend to use the models I am happy to provide personal support - just drop me an email!

The full procedure that uses the models as an input into CLUES/Sanitaiton21 is not yet published. Also the massflow model is not yet public on github because I am still testing it and improving it a little bit. I plan to finalize it by October.
I will post any updates here.

Dorothee

Dear Dean

The technologies which are currently implemented are all the once from the compendium (see ecompendium.sswm.info/sanitation-technologies ) + a few more "novel" options.
These "novel options" include among others:

• Struvite precipitation, vermi-composting toilet (inspired by the Biofil toilet),
• biochar production (inspired by the technology used by Sanivation in Kenya),
• pelletizing (inspired by the LaDePa process from Kwazulu-Natal).
• Liquid fertizlizer production from sorce-separated urine, a process developped by VUNA, a spin-off from Eawag ( www.vuna.ch/aurin/index_en.html ) .

The work is part of my PhD which I got fully funded through a scholarship and ETH/Eawag. I started to build a user interface but to make it fully functional and truly "usable" I would need some more time and money. I am currently exploring the demand (and related funding sources) for this. Please let me know if you have any hint for regarding the need and the funding of such a user interface!

Cheers, Dorothee