Examining the Disconnect Between Research and Innovation for WASH

Technologies

Caetano C. Dorea

Université Laval

1. Introduction

The majority (and increasing number) of humanitarian emergencies occur in developing

countries. Such countries are exposed to the same (if not worse) environmental

pressures of other nations, but typically they do not have the infra-structure to cope with

such changes. Studies indicate that both natural and manmade (i.e. violent conflicts)

disasters are on the rise1,2, mostly affecting those in developing countries. In addition to

the direct loss of lives and economic damage due to catastrophic events, the increased

health risks associated with communicable (i.e. diarrhoeal) diseases can have

devastating consequences. Such diseases are one of the major contributors to the

overall morbidity and mortality rates following a disaster34. Therefore, timely water

supply, sanitation, and hygiene promotion (WASH) interventions to reduce such risks

are essential5.

Many of necessary WASH relief intervention activities are technology-dependent (e.g.

water treatment and supply) and these must adapt to changing circumstances as a

crisis progresses from its critical immediate phases to post-emergency stages6 (Figure

1). This progression is usually characterised by an intense presence of relief resources

(e.g. funding and expertise) in the initial operations; allowing for particular technical

1 Oxfam International (2007) From weather alert to climate alarm. Oxfam Briefing Paper 108.2 Toole (1997) Complex Emergencies: Refugee and other populations. In: Noji (ed.) The public healthconsequences of disasters. Oxford University Press: 419-42.3 Waring & Brown (2005) The threat of communicable diseases following natural disasters: A public health response. Disaster Management & Response. 3(2): 41-47.4 Toole & Waldman (1997) The public health aspects of complex emergencies and refugee situations. Annual Review of Public Health, 18: 283–312.5 WHO (2005) Communicable disease control in emergencies: A field manual. WHO, Geneva, Switzerland.6 House & Reed (2004) Emergency water sources: Guidelines for selection and treatment. Third edition. Water, Engineering and Development Centre. Loughborough, UK.

solutions to be adopted. Such contexts may lend themselves useful for the adoption of

innovations during relief interventions.

Figure 1. Water quantity requirements in different phases of an emergency.

In non-emergency situations, growing populations and the associated environmental

pressures are setting the stage for rapid development in water- and wastewater-related

technologies (e.g. nanotechnologies, membrane science, analytical methods, etc.)

which are capable of delivering cleaner drinking water, improving wastewater treatment,

and providing cheaper and better sensors for contaminant detection/monitoring. Such

developments have been fuelled by incentives from governments, research councils,

and a opportunity- and market-conscious private sector. Yet, the benefits of these

cutting-edge solutions to the growing environmental challenges being faced are likely to

only be felt by those in richer nations. There has been limited progress in bringing the

benefits of such innovations to water treatment and supply operations in humanitarian

emergencies; where due to limitations of current technologies and field conditions the

level of service provided may not always be the best achievable.

Water treatment technologies exemplify the slow or non-existent effective uptake of new

developments in humanitarian emergencies. Many novel “high-tech” processes that are

efficient in the removal of particular contaminants in controlled conditions do not

become effective solutions in practice. Field experience suggests that some of the

commercially-available treatment “kits”, many do not seem to be compatible with

humanitarian relief requirements. Some of the common shortcomings are the inability of

these technologies to cope with field conditions typically encountered in resource-limited

humanitarian emergency contexts. Arguably, this is also a shortcoming of the

development process of these technologies.

The status quo suggests that what is researched by academia, what is available from

industry, and what is required by humanitarian organisations is disjoined with regards to

water supply technologies. This project seeks to examine issues posing barriers to

water supply and treatment technological transfer to relief agencies.

2. Objectives

The overall objective is to examine issues posing barriers to water supply and treatment

technological transfer to relief agencies and provide a strategy towards how to make

effective use of scientific developments in humanitarian emergencies. Specific aims are:

a) Identify and evaluate innovative technologies/processes currently being

developed or already commercially available with regards to their potential to effectively

contribute to public health engineering humanitarian responses;

b) Assess what universities and industries developing such technologies know

about the needs and environmental/resource constraints of emergencies.

3. Approach

The basic premise of this project is to triangulate the knowledge and perceptions

between humanitarian agencies, academia and industry sectors. To this end,

information was collected through a literature review and expert opinions.

4. Literature review

4.1Background

In the aftermath of catastrophic events it becomes necessary to re-establish the supply

of water to prevent outbreaks of water- and excreta-related diseases7 (alongside

sanitation and hygiene interventions). Such circumstances require the supply of

sufficient quantities of water of adequate quality. In order to meet the public health

intervention aim of prevention/reduction or diarrhoeal diseases during emergencies with

regards to water supply, the recommended priority8,9 is for larger quantities of water (i.e.

for personal hygiene) of “safe” quality (no thermotolerant coliforms per 100 mL, 0.5

mg/L of free chlorine residual, and turbidity < 5 nephelometric turbidity units – NTUs). In 7 Mara & Feachem (1999) Water- and Excreta-Related Diseases: Unitary Environmental Classification. Journal of Environmental Engineering-ASCE, 125(4): 334-339.8 The Sphere Project (2011) Humanitarian Charter and Minimum Standards in Disaster Response, OxfamPublishing9 WHO (2005) Communicable disease control in emergencies: A field manual. WHO, Geneva, Switzerland.

other words, a larger quantity of relatively good (safe) quality water is better than a

small quantity of very high quality water. In such cases, the quantity of water is

prioritised over the quality. This does not imply a neglect of aesthetic and

microbiological quality considerations. Yet, it is the case that water-related disease

transmission in emergencies is as much likely due to insufficient quantities for personal

and domestic hygiene as to contaminated water supplies10; thus defining the

requirements for emergencies.

Figure 2. Examples of emergency situations where water treatment systems are

destroyed (left – Indonesia, Tsunami response 2005) or inexistent (right – Chad, 2005).

In many instances, the facilities for basic requirements, such as an adequate water

supply, are contaminated (e.g. unprotected wells in floods), destroyed (e.g. water

treatment plants in Iraq) or not available (e.g. in the case of forced migrations) (Figure

2). When the (re-)establishment of adequate water supplies is beyond the capacity of

local authorities, aid from external relief agencies is warranted.

10 The Sphere Project (2011) Humanitarian Charter and Minimum Standards in Disaster Response, Oxfam Publishing.

Figure 3. Use of groundwater “wadi” source (Chad).

The selection of a water source is of critical importance to the emergency response.

The choice should be based on factors such as the quality of the source, the demand to

be catered for and the resources available. Although the safest option is usually

groundwater (Figure 3), it may not be available in sufficient quantities or at a suitable

distance to serve the demand. In many cases the quickest alternative is a surface water

source. However, these are usually the most polluted (Figure 4). Water source selection

is regarded in more detail elsewhere11,12.

11 House & Reed (2004) Emergency water sources: Guidelines for selection and treatment. Third edition. Water, Engineering and Development Centre. Loughborough, UK.12 Davis & Lambert (2002) Engineering in Emergencies: A practical guide for relief workers, 2nd edn, ITDG Publishing, London, UK.

Figure 4. Turbid surface water source (Gonaives, Haiti).

Groundwater sources typically only require disinfection prior to distribution; accordingly,

it is not considered here. Emergency drinking water treatment is mainly intended for

surface waters. This is usually achieved with packaged water treatment systems, also

referred to as “kits,” for a centralised bulk water treatment production. However, more

recently, decentralised emergency water treatment interventions with point-of-use

(POU) water treatment alternatives have been used in humanitarian interventions. The

review of the water treatment unit processes is based on kits and approaches

commonly used in emergencies as well as innovations with potential application in

humanitarian contexts.

4.2Landscape of current water treatment approaches

Emergency water treatment options can be broadly divided in to three categories:

modular, mobile, and POU treatment alternatives13. This division is based on previous

classifications14,15 that did not include the POU category. Modular kits refer to those

treatment systems which are assembled on location. Mobile units are those mounted on

to a self-contained trailer or portable container; in theory, they require a comparatively

short setup time. A third category, POU water treatment, consists of household level

water treatment interventions. Typically, emergency water treatment processes rely on

some form of particle removal (i.e. turbidity reduction) to conform with the aesthetic

recommendations (i.e. < 5 NTU) and also to facilitate terminal disinfection that can be

negatively affected by high particle loadings. Thus, turbidity is an important operational

parameter to consider in the assessment of emergency water treatment alternatives.

Modular systems. In general, this approach relies on coagulant-based clarification

processes to achieve turbidity reductions prior to terminal disinfection. Perhaps the most

common and simplest form of emergency water treatment is batch clarification (Figure

4). This mode of chemically assisted clarification is carried out in storage tanks (e.g. 11,

45, 70, and 90 m3) by adding the coagulant stock solution to the incoming water. The

settled water is then decanted, stored and disinfected prior to distribution. This form of

treatment approach has remained largely unchanged, which is one of its attractive

features (i.e. simplicity and replicability), apart from a few simple process

13 Dorea, Bertrand & Clarke (2006) Particle separation options for emergency water treatment. Water Science & Technology, 53(7): 253-60.14 Nothomb. (1995). Portable water treatment units for emergency situations. MSc thesis, Loughborough University, Loughborough, UK.15 House & Reed (2004) Emergency water sources: Guidelines for selection and treatment. Third edition. Water, Engineering and Development Centre. Loughborough, UK.

improvements16. Despite limited process control, turbidities in the hundreds can be

reduced to what is considered to acceptable by the Sphere Standards (i.e. 5 NTU).

Figure 5. Batch water treatment system (sedimentation tanks in background).

Another variant to batch modular systems are ones that operate on a continuous mode.

However, there are none that are currently being used. A notable example was the

Oxfam Field Upflow Clarifier17 (Figure 6). The rationale behind this alternative was to

benefit from the good turbidity reduction efficiencies of the coagulant-based clarification

without the frequent blockages typical of media filtration that can occur when high levels

or peaks of particulate loadings occur18. Such a process was in line with the emergency

water treatment objective of high production yield of safe quality levels. This is thought

to be due to the close involvement between the end-users (i.e. relief agencies) and the

developers (i.e. academic sector). Despite its proven field efficiency, the setup of this 16 Dorea (2007) Simple improvements for emergency batch water treatment. Waterlines, 26(1): 17-9.17 Dorea, Luff, Bastable & Clarke (2009) Up-flow Clarifier for Emergency Water Treatment. Water and Environment Journal, 23(4): 293-9.18 Clarke, Crompton & Luff (2004) A physico-chemical water treatment system for relief agencies. Water Management, 157(4): 211–6.

water treatment option was deemed too complicated by relief agencies – being this the

reason for its discontinuation. However, the “Clarifier” was worth mentioning in this

review as the collaborative approach during its development was thought to be a key

factor in its relatively successful field performance.

Figure 6. Oxfam field upflow clarifier kit (discontinued).

Mobile systems. Traditionally, these are filtration (i.e. media or membrane) based

systems. Mobile media filtration units have two variants: sand (or media) pressure filters

(Figure 7) or membrane filters. In membrane mobile filtration units pressurised water is

passed through a semi-permeable membrane, removing particulates in a manner

similar to other media filtration processes. In general, such units are vulnerable to high

raw water turbidities, as high particulate loadings cause such systems to have short

filtration cycles19. This affects the overall net production yield, which could be an issue,

19 Dorea, Bertrand & Clarke (2006) Particle separation options for emergency water treatment. Water Science & Technology, 53(7): 253-60.

as one of the treatment objectives of emergency water supply is the provision of

adequate amounts of safe water for hydration and hygiene purposes.

Figure 7. Mobile pressure filtration system (P4000 – Aquaplus, India).

Point-of-use (POU) techniques. This decentralised (i.e. at a household level) approach

can take a variety of forms such as boiling, ceramic filters, coagulant/disinfectant

sachet-type products20 (e.g. PUR, WaterMaker, Bishan Gari, etc.), chlorination

tablets/solutions21 (e.g. Aquatabs, WaterGuard, etc.), solar disinfection (SODIS), and

biosand filtration. Notably, for the most part, these techniques address water treatment

for hydration only. A relief programme would still need to cater for a water supply for

hygiene purposes. The successful implementation of this approach requires time and

resources to effectively train beneficiaries on the correct and sustained use of POU

techniques. Thus, also considering the variability in emergency types and durations, not 20 Marois-Fiset & Dorea (2013) Sachet-type point-of-use (POU) water treatment product comparison for emergencies. In: 36th WEDC International Conference, Nakuru, Kenya.21 McLennan, Peterson & Rose (2009) Comparison of point-of-use technologies for emergency disinfection of sewage-contaminated drinking water. Applied & Environmental Microbiology, 75(22): 7283-6.

all techniques may be appropriate for relief interventions. POU training requirements

may hinder implementation efforts of household-based water treatment interventions in

humanitarian contexts, particularly during the first phases of an emergency response.

These difficulties were reported in the Indian Ocean tsunami emergency response when

the implementation of some POU water treatment activities were attempted22.However,

there is evidence that POU water treatment and safe storage techniques can be

effective interventions to prevent diarrheal diseases in humanitarian emergency

contexts23.

Water quality analysis. An important aspect of water treatment is the attainment of safe

drinking water quality levels as recommended by The Sphere Project. Currently, the

measurement of the four critical water quality parameters (i.e. free chlorine residual, pH,

faecal bacteria indicator organism, and turbidity) is typically done with field-adapted

techniques such as the Oxfam-DelAgua water quality test kit24 and its commercially-

available variants. Other proposed alternatives for emergency applications to the

traditionally used faecal bacteria indicator organisms (e.g. thermotolerant coliforms, E.

coli, etc.) determinations based on the membrane filtration technique are tests such as

the H2S (presence/absence) test, Colilert tubes (presence/absence), and the Dipslide

test25. Obviously, other analytical techniques exist, but only those considered or

proposed for humanitarian applications were considered here. A key challenge in water

22 Clasen, Smith, Albert, Bastable & Fesselet (2006) The drinking water response to the Indian Ocean tsunami, including the role of household water treatment. Disaster Prevention & Management, 15(1), 190-201.23 Lantagne & Clasen (2012) Use of household water treatment and safe storage methods in acute emergency response: case study results from Nepal, Indonesia, Kenya, and Haiti. Environmental Science & Technology, 46:11352–60.24 Lloyd, Wheeler & Snook (1985) A low-cost portable water testing kit for developing countries. Water Science & Technology, 17(8): 1369-70.25 Oxfam GB (2006) Water quality analysis in emergency situations. Technical Brief (OXFAM – TB3).

quality analysis with regards to faecal pollution detection is the speed in which results

can be obtained. To date, conventional methods listed above typically produce results

within 18 to 24 hours. Notably, water quality analysis results are difficult to come across,

particularly in published and grey literature. This raises questions with regards to the

actual use of such kits and the information they yield.

4.3Landscape of innovations in emergency water treatment

Mobile systems. Recently, the principles of inclined plate settling have been adapted for

use in humanitarian emergencies with a novel mobile treatment system26 (Figure8). This

system has been developed with the aim of overcoming the limitations of filtration-based

methods (i.e. vulnerability to high particulate loadings), whilst taking advantages of the

relative high production yields conferred by continuous coagulant-enhanced clarification

and the relatively rapid setup times of mobile systems. Its development was described

as an improvement on the relative field success of the Oxfam Clarifier described earlier.

However, at the time of writing, such a system had not yet been deployed in an

emergency situation; despite its promising test results27.

26 Dorea & Bourgault (2013) Inclined plate settling for emergency water treatment. In: 36th WEDC International Conference, Nakuru, Kenya.27 Dorea, Williams, Boulay-Côté, Bédard & Bouchard (2014) Inclined plate settling for emergency water treatment: towards optimisation. In: 37th WEDC International Conference, Hanoi, Vietnam.

Figure 8. Prototype of an inclined plate settler for emergency response (Pune, India).

Point-of-use (POU) techniques. In general, the adoption of “conventional” POU

techniques are not yet mainstream in humanitarian emergencies, with the exceptions of

water boiling and chlorine disinfection. However, there have been innovations in this

sector, which have been proposed as potential alternatives for humanitarian relief.

Examples of such innovations can be found in recent applications of silver nanoparticle-

based technologies28,29. However, these technologies remain confined to the laboratory

and require further development before their assessment in the field.

Semi-decentralised water treatment. In order to take advantage of the water treatment

advantages of coagulation-based clarification treatment approaches and overcome the

logistical limitations of POU techniques, a semi-decentralised water treatment approach

has been proposed. This water treatment variant is in essence a scaled-up version of 28 Dankovich & Gray (2011) Bactericidal paper impregnated with silver nanoparticles for point-of-use water treatment. Environmental Science & Technology, 45(5): 1992–8.29 Loo, Fane, Lim, Krantz, Liang, Liu & Hu (2013) Superabsorbent cryogels decorated with silver nanoparticles as a novel water technology for point-of-use disinfection. Environmental Science & Technology, 47(16): 9363–71.

the coagulant/disinfection POU approach to treat volumes of 200 to 1000 L at a time. A

few commercially-available products have already been identified (e.g. Watermaker and

Tigitech). Preliminary laboratory tests have demonstrated the potential of this

approach30. However, no data is available on their field use.

Water quality analysis. A few innovations in water quality analysis have appeared

recently. A novel and simplified water testing kit, the Aquatest31, has been developed

and is proposed as a low-cost and simpler alternative to DelAgua-type test kits.

However, no field evaluations of this innovation have been published to date. Another

innovation relating to water quality analysis is the use of mobile technologies for

reporting and georeferencing purposes32.

Information flow. In addition to the technologies themselves, recently, several

innovations have also sprung with the intention of improving the flow of information

mainly regarding water and sanitation issues. That is, in this case, the innovation was in

the way technical information could reach the field. In most cases the delivery of

information was made through an online platform. Examples include online forums such

as www.aidworkers.net (now defunct), www.watersanitationhygiene.org (now defunct)

and www.susana.org (Sustainable Sanitation Alliance – mainly devoted to sanitation). In

these forums, although they were not necessarily specifically dedicated to water and

sanitation issues in humanitarian contexts, registered users could share information or

post questions that could be answered by peers, which included registered users from a

30 Dorea & Jalaber (2014) The potential of semi-decentralised bulk water treatment for emergency relief. Journal of Water, Sanitation and Hygiene for Development (in press).31 Gundry (2008) Low cost water test for developing countries – a preparatory study. Publishable Final Activity Report.32 Rahman, Khush & Gundry (2010) Aquatest: Expanding Microbial Water Quality Testing for Drinking Water Management. Drinking Water Safety International, April: 15-17.

variety of backgrounds. Such forums seem to be relatively popular at one point.

However, seeing that two out of three are no longer functional, questions can be raised

about the sustainability of such innovations. The latter example (www.susana.org) has

kept its existence and usefulness due to external funding for its maintenance and

moderation. Perhaps this was a pivotal aspect of its relative success. More recently, the

Knowledge Point project was launched (www.knowledgepoint.org) in which user queries

are answered online by a select panel of experts (i.e. not open general public). This

initiative was specifically intended for humanitarian emergencies. However, it is fairly

recent and thus difficult to ascertain its role in the diffusion of knowledge related to

humanitarian water and sanitation.

4.4Discussion

Although water treatment and supply innovations are well-intentioned, many do not

perform well in the field33, thus not properly serving disaster victims. One of the main

issues identified was the lack of compliance with water treatment and supply objectives

for humanitarian contexts (i.e. The Sphere Project). Many technologies fail to deliver

suitable aid, as they seem to be mainly focused on water quality without the necessary

consideration of the supply of adequate amounts of water. This can be attributed to

inadequate design due to a lack of consultation with end-users (i.e. humanitarian

agencies) or due to the misuse of the technologies. That is, many systems currently

used for humanitarian emergencies have been initially developed for military purposes,

where the design criteria34 is aimed at the provision of highly purified water solely for 33 Luff & Dorea (2012) Bulk Water Treatment Unit performance – for the cameras or the community? Waterlines, 31(1-2): 53-66.34 Quémerais (2006) Water collection purification system: Identifying CF capabilities and requirements and assessing off-the-shelf purification systems. Technical report, Defence R&D Canada.

drinking purposes of military personnel. Therefore, many systems are not considered to

be fit-for-purpose for humanitarian relief contexts.

There has recently been a surge of funding opportunities for the development of

innovations. Whereas many of these are not specific with regards to the field of

application, allowing for a variety of innovations including those for humanitarian

purposes, others are focused on humanitarian causes (e.g. Humanitarian Innovation

Fund, OCHA, ELRHA, and Research for Health in Humanitarian Crises). Such

opportunities will be a good incentive for the development of innovations for the sector.

It is interesting to note the different funding models being utilised and the possible

influence they can have on the success of innovations. For example, grants from the Bill

& Melinda Gates Foundation are designed to support the development of “bold ideas”

through an open call seed funding of many unconventional (and perhaps with a high risk

of failure) ideas. After an initial period, those projects that have demonstrated evidence

of their potential to succeed are then awarded more substantial grants for the further

development and scaling-up of the innovations. Another interesting example is that of

the Humanitarian Innovation Fund, which has specific calls for funding at different

stages of the innovation process (i.e. recognition, innovation, development,

implementation, and diffusion). Finally, it is worth mentioning the model adopted by

Grand Challenges Canada, which seems to be somewhat mirrored on the Bill & Melinda

Gates Foundation model. However, one interesting differential is the encouragement of

partnerships. In this case applicants from developed countries must partner with

developing country organisations to ensure the field testing and robustness of the

innovations. On the other hand developing country applicants are also encouraged to

partner with experienced project mentors aimed at providing amongst other things

project management experience to locally-generated ideas.

5. Expert opinions

Exploring the relationship between NGOs, Industry and Academia. Working

relationships between each sector were highly variable with regards to examples that

were identified. From the conducted survey, in many cases it was apparent that both

academia and NGOs had a better understanding of each other’s viewpoints. However,

the perspective of the industry respondents indicated that not always the needs and

constraints of the practitioners were understood. In addition, it was reported by some

industry respondents that there was a lack of opportunities to present innovations and a

reluctance to assist in product development. On the other hand, a respondent from a

major relief agency contested that they were constantly “bombarded” by manufacturers

and sales people claiming to have the “panacea” to their water problems. Typically, it

was said that these were water treatment products that could deliver water of an

extreme degree of purity, but usually in a very limited volume (and relatively high cost).

These solutions many times were innovative, but failed to recognise the double-pronged

objective of emergency water supply: adequate quantities and safe quality. To some

extent this may be the case. However it is unclear if the reasons are due to a sector-

wide breakdown in communication or individual cases of misunderstandings.

By understanding knowledge gaps, each sector may be able to establish improved

working relationships that allow greater flow of novel ideas and innovations into the

marketplace. In addition, there has also been an observation from responses that

technologies experience a greater reception from NGOs if a rapport has already been

built between the organizations involved. This may present a difficulty for those without

such circles to establish a competing technology.

Needs and constraints of disaster affected communities. The requirements and the

constraints of field work is an issue of paramount importance for an effective uptake of

innovations intended for disaster relief. It became apparent through interviews that

many times assumptions are many times used during the development of innovations,

rather than field trials. When the needs of practitioners are not accounted for, a crucial

aspect in the implementation of technologies intended for humanitarian relief would be

neglected. Such is an issue that could be resolved if better inter-sectorial (i.e. NGO,

academia, industry) communication is improved.

Analysis of current and required knowledge base for uptake of new technologies.

Humanitarian practitioners have evolved from individuals equipped with generic

technical skills and good intentions to sometimes now relatively more highly-specialised

professionals with relief-focused post-graduate preparation. Such differences are

possibly due to the changes in how humanitarian relief is conducted too. Changes have

also occurred in the training sector. Yet, in order to assimilate innovations it is plausible

that a parallel change in humanitarian skills and know how may be needed.

Currently available training courses are abundant and range in durations, format and

contents, catering for varied backgrounds. Many of the short courses consist of

preparatory sessions for professionals wanting to start a humanitarian career, practicing

professionals aiming to refresh concepts. Longer courses are mainly postgraduate level

programmes with a varied curriculum and with scope to incorporate latest thinking and

expand the core knowledge of trainees on fundamental science and engineering

concepts that could allow innovations to be more effectively utilised in humanitarian

emergencies. However, many of these do not necessarily offer field experience, which

could limit somewhat their value to professionals with no previous humanitarian

experience.

6. Concluding remarks

Several issues were identified as contributing to the lack of communication between

NGOs, academia and industry regarding humanitarian water treatment innovations. If

this information flow could be improved, knowledge of innovations would contribute to a

step change in humanitarian practice towards more effective solutions that are aimed at

“the best we can achieve,” as opposed to “the worst we can tolerate.” In order to

streamline new technologies from blueprints to effective solutions for humanitarian

emergencies, aspects of this relationship between humanitarian relief organisations,

universities and industry must be acknowledged and addressed.

This report addressed humanitarian water treatment innovations. However, sanitation is

a sector that overall is lagging behind. Far fewer options exist currently and this is also

reflected on the existence of innovations in this sector. Similar analyses could be

applied to emergency sanitation.