The Sanitation Technology Platform

Please Note: This report is a good faith effort by RTI International to accurately represent information available via secondary and

primary sources at the time of the information capture. The report is confidential and proprietary and only for internal uses and not for

publication or public disclosure.

APARTMENTS IN INDIAA Small-Scale Survey

AUGUST 2015

Background

Survey Methodology

General Descriptive Statistics

Building Feasibility Analysis

User Sanitation Perceptions

Study Limitations

Appendix

TABLE OF CONTENTS

TASK OBJECTIVES

3

Understanding the features of apartment housing in target settings will be important to designing and testing systems. Within this task, we have undertaken a modest mixed methods qualitative/quantitative study to identify and assess structural features in the city of Coimbatore, Tamil Nadu to provide insight into the suitability for installation and testing of new sanitation technologies.

This study aimed to quantify residential structures (apartment buildings) that could be suitable for testing of a decentralized wastewater treatment technology that connects to existing water and sewage lines, treats incoming waste and wastewater streams, and uses recycled water for flushing.

A combination of observational data collection and survey-based data collection was used, focusing on the following key topics:

• Structural features (e.g., size, floors, units), occupancy, and history of each building

• Quality, cost, and usage of current water, sanitation, and electrical services by residents

• Resident and apartment building and managers’ receptiveness to wastewater treatment technologies

For partners, STeP sought to qualify and quantify apartment buildings and features in Coimbatore, India.

4

The mixed methods survey of 400+ structures included observational and interview questions.Observations & InterviewsEnumerator observations of external building structure (validation measure for system requirements)

Building worker interviews (one or more landlords, caretakers, or building managers) to learn of structure and utilities

• Tours undertaken of potential installation sites on ground floor and roof

• Enumerator measured and sketched floor plans and captured photos of potential sites

Tenant interviews to capture utility availability, quality, and pricing details and participate in preliminary choice experiment

• Gauged attitude towards water reuse and wastewater treatment systems

SURVEY METHODOLOGY

5

Population was defined as residential apartment buildings with 2+ floors.Population• Target population was defined as residential

apartment buildings in Coimbatore city with at least two floors.

• A mix of probability and non-probability methods were used to obtain a sample, as no pre-existing list of apartment building characteristics was available.

Sampling• Stratified sample by five administrative zones of

Coimbatore; allocations made roughly in proportion to # of buildings in each zone.

• Sampled 20 wards per zone. Randomly selected five wards from 20.

• Used quota design (non-probability method): fieldwork teams were assigned 8-21 buildings to sample within wards.

• Constrained by lack of sampling frame; additional intent to ensure inclusion of diverse building types in survey.

SURVEY METHODOLOGY

Map of Coimbatore city (pre-2011 five-zone design)

6

Utility coverage among sampled buildings was high. Nearly all tenants paid for electricity, while 40% and 60% paid for sewage and water respectively.Observation Counts Tenant-reported Socio-economic Characteristics

SURVEY DESCRIPTION –SUMMARY STATISTICS

Building Workers Interviewed 393

Landlord 79.1%

Caretaker 39.9%

Developer 2.8%

Maintenance Worker 1.8%

Building Secretary 0.3%

Other 0.3%

Tenants interviewed 1191

# of residential units 6 to 12

# of units per floor 2 to 4

# of residents per unit 3 to 5

# of residents per building 18 to 48

Occupied by owner* 64.1%

Rented/leased out* 83%

State-run apartment* 5.9%

Rental cost per month (Rs.) 3000 to 5000

Monthly service fee 42.4%

Water 62.0%

Sewer 39.8%

Electricity 90.7%

TV 82.4%

# of tenancy years 1 to 4

Monthly household income (Rs.) 11,000 to 20,000

Monthly cost for services/utilities 400 to 10000 20 40 60 80 100

Piped water supply

Water tank

Municipal sewage line

Septic tank

Electricity

Building Utilities Availability (%)

*reported by building worker

Background

Survey Methodology

General Descriptive Statistics

Building Feasibility Analysis

User Sanitation Perceptions

Study Limitations

Appendix

TABLE OF CONTENTS

8

A range of physical infrastructure and utilities criteria were used to determine suitability of buildings; select criteria evolved some throughout the study.

BUILDING FEASIBILITY ANALYSIS - CRITERIA

Primary drivers behind the changes were need for flexibility in the retrofitting process to engineer around physical barriers or constraints.

Initial Criteria Final CriteriaWater supply connection

Sewage connection

Electricity connection

>80% water supply

>80% electricity connection

Water supply connection

Sewage connection

Electricity connection

>80% water supply

>80% electricity connection

Separate toilet wastewater lines

Exposed water supply lines

Exposed blackwater lines

Exposed toilet wastewater lines

2 waste drain pipes

Automatic flush toilets

Separate toilet water lines if auto-flush

Exposed toilet water lines if auto-flush

Exposed blackwater lines

Preferred:

Separate toilet wastewater lines

Exposed toilet wastewater lines

Roof space

Roof weight capacity

Roof routine access

Ground floor space

Ground floor routine access

Roof space

Roof weight capacity

Roof routine access

Ground floor space

Ground floor routine access

2-5 floors

18-25 occupancy count

Parking underneath building

2-7 floors (2-5 floors preferred)

18-25 occupants preferred

9

Additional criteria included dimensions that would become relevant during installation and testing and included user data.User data• Routine access to building, i.e. unrestrictive

building security

• # of daily sanitation events (urination and defecation) at home toilet to anticipate load on sanitation system

• Inputs in toilet aside from human waste (e.g. cleaning products)

BUILDING FEASIBILITY ANALYSIS - CRITERIA

BUILDING FEASIBILITY ANALYSIS –IDENTIFYING SITES

10

393

340

296

296

296

288

288

286

274

139

139

139

139

139

139

134

125

125

123

21

0 50 100 150 200 250 300 350

Total

Water supply

Sewage connection

Electricity connection

>80% electricity

>80% water

Flush system

Toilet water line

Exposed toilet water line

Exposed blackwater drain

Toilet wastewater line

Exposed toilet wastewater line

Roof space

Roof weight capacity

Roof access

Ground floor space

Ground floor access

Floors: 2-7

Floors: 2-5

Occupancy: 18-25

BUILDING COUNT

Total

Preferred

Pour-flush

Autoflush

Site Features by Total Count

11

Approximately 30% of sampled buildings were ‘good fits’ for an external wastewater treatment system as defined within criteria.

• Further analysis suggests suitable buildings generally did not tend to cluster by geography or income level of residents

• Zone 3 (central) was less likely to have the appropriate drains for installation in comparison to other areas

• Income was an insignificant factor

• Within this data set, findings suggest suitable buildings may be interspersed throughout Coimbatore

BUILDING FEASIBILITY ANALYSIS –IDENTIFYING SITES

Background

Survey Methodology

General Descriptive Statistics

Building Feasibility Analysis

User Sanitation Perceptions

Study Limitations

Appendix

TABLE OF CONTENTS

13

Participants asked to rate satisfaction with building’s current treatment of sewage.

High level of satisfaction: Over 85% of respondents reported they were

‘somewhat’ or ‘completely satisfied’ with how their building was currently treating

sewage.

Tenant satisfaction with sewage treatment (%)

USER SANITATION PERCEPTIONS

Completely dissatisfied 7.9

Somewhat dissatisfied 3.5

Neutral 0.3

Somewhat satisfied 16.5

Completely satisfied 68.9

Refused 2.8

Don’t know 0.1

Total 100.0

14

Moderate interest among tenants for using reused water for flushing.• Tenants participated in informal choice

experiment: asked whether interested in using reused water for flushing

• Limited information given – implicitly told to hold other aspects of technology and treatment constant

• Offered successively lower cost options in comparison to current systems

• Moderate elasticity of demand for reused water

• Willingness-to-pay only ranged from 37% (at highest price) to 60% (for free)

• Nearly 40% of respondents were resistant to switching to water reuse for flushing even at zero cost

• Low responses could relate to satisfaction with current services, low environmental awareness, religious or cultural stigmas around water reuse, or other factors

Tenant interest in reused water for flushing by relative price point (%)

USER SANITATION PERCEPTIONS

25% less than

current cost

50% less than

current cost

75% less than current

costNo cost (free)

Yes 37.4 40.1 45.7 60.0

No 56.1 54.4 50.0 35.4

Refused 6.4 5.4 4.0 4.5

Don’t know 0.2 0.2 0.4 0.3

Total 100.0 100.0 100.0 100.0

15

Among yea-sayers, greater environmental and hygiene awareness may be drivers behind demand for reused water.

Attitude toward reused water• Respondents from higher income households were

more willing to pay for reused water - could be proxy for education or other unobserved characteristics

• Participants who are water-stressed or display higher hygiene-awareness have higher WTP for reused water

• Those using automatic flush toilets and those who urinate more frequently per day are less willing to use reused water for flushing

• Trends should be investigated further with qualitative and quantitative research

• May indicate an apprehension towards lowering quality of existing sanitation

• Estimation exercise must be supplemented by further research to capture unobserved variables

USER SANITATION PERCEPTIONS

Background

Survey Methodology

General Descriptive Statistics

Building Feasibility Analysis

User Sanitation Perceptions

Study Limitations

Appendix

TABLE OF CONTENTS

17

Feasibility study and preliminary assessment of user reception to water reuse subject to sampling and data limitations.

• Building sampling was non-random and cannot represent Coimbatore, Tamil Nadu, or India more broadly

• Willingness to pay exercise for water reuse suggests there may be moderate resistance to this feature, but a broader range of user characteristics need to be gathered to understand motivations behind choices

• Findings may not be indicative of actual willingness to pay as respondents may not have understood the choice questions

• Responses are subject to incomplete understanding of wastewater system, as little information was presented aside from cost and the water reuse feature

STUDY LIMITATIONS

Background

Survey Methodology

General Descriptive Statistics

Building Feasibility Analysis

User Sanitation Perceptions

Study Limitations

Appendix

TABLE OF CONTENTS

• Percentage of buildings meeting each criteria• Preliminary analysis of “suitable sites” clustering by

region and income level• Preliminary regression analysis of WTP for water

reuse among tenants

19

Percentages of buildings meeting each criteria.

Structural features (reported by building worker) Installation sites (reported by building manager)

APPENDIX A.

Ground floor Percent

Space on ground floor

(3.5m x 5m x 2.5m)

98.7

# of sites 1 to 2

Floor material

(multiple answers, all sites)

Concrete/cement 94.9

Tile 8.1

Marble 0.7

Other 3.9

Indoor 58.6

Covered 76.2

Accessible once/week for maintenance 86.3

Roof

Space for water tank (3.5m x 2.5m) 99.5

Can support 800kg 100

Number of sites 1 to 2

Roof access for routine maintenance 99.5

Stairs 99.5

Elevator 1.3

Other 1.3

Percent

Total 100

Utilities

Water supply connection 86.5

Sewage connection 87.8

Electricity connection 100

Toilet water line 82.7

Toilet sewage line 74.6

Exposed water supply line 35.9

Exposed wastewater drains 55.2

Exposed toilet wastewater drain 40.5

Exposed toilet water line 31.8

Exposed blackwater line 30.0

>80% water supply 97.7

>80% electricity connection 100

Building features

Floors: 2-5 90.8

Floors: 2-7 93.9

Occupancy: 18-25 17.6

Occupancy: 18-40 30.0

Parking under building 64.6

Automatic flush toilets 12.2

20

Preliminary analysis of suitable site clustering by region and income-level.Likelihood of fulfilling each set of criteria (for pour-flush and auto-flush buildings)

APPENDIX B.

(1) (2) (3) (4) (5) (6) (7)

VARIABLES Utilities Drains (auto-

flush)

Drains (pour-

flush)

Installation site

(auto-flush)

Installation site

(pour-flush)

Occupancy

(auto-flush)

Occupancy

(pour-flush)

Income

quartile0.0814* 0.0222 0.0150 -0.00147 0.0391 -0.00260 0.0169

(0.0448) (0.0194) (0.0518) (0.0139) (0.0506) (0.00264) (0.0271)

Zone 2 -0.0125 -0.00322 -0.0908 0.00886 -0.0699 0.000120 -0.0799**

(0.0499) (0.0290) (0.0788) (0.0266) (0.0784) (0.000223) (0.0394)

Zone 3 -0.377*** -0.0190 -0.219*** -0.0119 -0.232*** 0.000638 -0.0946**

(0.0583) (0.0228) (0.0674) (0.0169) (0.0659) (0.000672) (0.0376)

Zone 4 -0.152*** 0.000488 -0.0546 0.0110 -0.0980 0.0109 -0.0546

(0.0555) (0.0267) (0.0731) (0.0245) (0.0711) (0.0110) (0.0408)

Zone 5 -0.170** -0.0134 -0.129 -0.0217 -0.157* 0.000429 -0.0662

(0.0733) (0.0291) (0.0889) (0.0150) (0.0859) (0.000492) (0.0465)

Constant 0.882*** 0.0278 0.425*** 0.0223 0.398*** 0.000601 0.106***

(0.0345) (0.0189) (0.0534) (0.0167) (0.0528) (0.000617) (0.0331)

N 393 393 393 393 393 393 393

R-squared 0.114 0.005 0.029 0.007 0.033 0.009 0.024

Robust standard errors in parentheses

*** p<0.01, ** p<0.05, * p<0.1

21

Preliminary regression analysis of WTP for water reuse among tenantsAttitude toward reused water – analysisOrdered logit regression of WTP for Reused Water for Flushing[1] [2]

Note: Standard errors in parentheses;*** p<0.1, ** p<0.05, * p<0.01;

[1] Willingness to pay was transformed into an index spanning 0 to 4 using the choice experiment reported on slide 14, with 0 representing complete unwillingness to pay, and 4 representing the highest willingness to pay (25% less than current cost). We specified an ordered logistic regression that accounted for this ranking. Of note, a more flexible model is preferred, such as a generalized ordered logit, as the parallel regressions assumption (that preference relationships remain constant between all levels of WTP) is violated by the ordered logit reported here. These results must be taken tentatively, though we also note that statistical significance and direction of coefficients remain largely unchanged across different model specifications.

[2] Approximately 5% of respondents ‘switched’ their preferences between cost levels – i.e. were WTP a higher amount, then switched to ‘no’ for a lower cost. As these divergences from rational economic theory were minimal, preferences were coded as cumulative in the WTP index variable. That is to say, higher WTP was automatically coded as also WTP for lower levels. Contrary cases may have occurred due to misunderstanding of the question, or other factors not captured by this exercise.

APPENDIX C.

VARIABLES WTP

Renting -0.142

(0.280)

Any renovations within past year -0.134

(0.221)

# of building residents 0.00131

(0.00105)

# of apt. residents -0.0707*

(0.0403)

Ln(Income) 0.490***

(0.164)

Monthly rent -1.38e-06

(3.12e-05)

Monthly water fee 0.00590***

(0.00143)

Length of stay -0.00658

(0.0185)

Satisfaction with sewage service 0.324***

(0.0673)

Accesses additional water source 0.374**

(0.168)

# of urination events/day -0.170***

(0.0270)

# of defecation events/day -0.0459

(0.0983)

Importance of toilet in building choice 0.0854

(0.184)

Frequency of toilet cleaning 0.237***

(0.0882)

Automatic flush -0.537**

(0.270)

Zone Fixed Effects Yes

Observations 833

CONTACTS

Brent Rowe, MAbrowe@rti.org

Charles Lau, PhDclau@rti.org

Anushah Hossain, BAanhossain@rti.org

Brandy Salmon, PhDbsalmon@rti.org