| Literature DB >> 27667863 |
Michael B Fisher1, Katherine F Shields1, Terence U Chan2, Elizabeth Christenson1, Ryan D Cronk1, Hannah Leker1, Destina Samani3, Patrick Apoya3, Alexandra Lutz4, Jamie Bartram1.
Abstract
Safe drinking water is critical to human health and development. In rural sub-Saharan Africa, most improved water sources are boreholes with handpumps; studies suggest that up to one third of these handpumps are nonfunctional at any given time. This work presents findings from a secondary analysis of cross-sectional data from 1509 water sources in 570 communities in the rural Greater Afram Plains (GAP) region of Ghana; one of the largest studies of its kind. 79.4% of enumerated water sources were functional when visited; in multivariable regressions, functionality depended on source age, management, tariff collection, the number of other sources in the community, and the district. A Bayesian network (BN) model developed using the same data set found strong dependencies of functionality on implementer, pump type, management, and the availability of tools, with synergistic effects from management determinants on functionality, increasing the likelihood of a source being functional from a baseline of 72% to more than 97% with optimal management and available tools. We suggest that functionality may be a dynamic equilibrium between regular breakdowns and repairs, with management a key determinant of repair rate. Management variables may interact synergistically in ways better captured by BN analysis than by logistic regressions. These qualitative findings may prove generalizable beyond the study area, and may offer new approaches to understanding and increasing handpump functionality and safe water access.Entities:
Keywords: borehole; function; manage; pump; sustain; well
Year: 2015 PMID: 27667863 PMCID: PMC5019267 DOI: 10.1002/2014WR016770
Source DB: PubMed Journal: Water Resour Res ISSN: 0043-1397 Impact factor: 5.240
Figure 1Map of study area.
Figure 2Conceptual model of water source functionality. Determinants marked with an asterisk are significant (p < 0.05) in multivariable regressions; determinants marked with a dagger are significant (p < 0.1) in multivariable regressions; determinants in dashed boxes and gray type were not directly measured.; green arrows (→) indicate effects predicted to modify the rate of repair; red arrows (→) indicate effects predicted to modify the rate of failure; thin arrows (→) indicate indirect effects on functionality; thick arrows (→) indicate direct effects on functionality.
Figure 3Bayesian network model. This Bayesian network model depicts the overall “baseline case” for the model, with the states of all nodes representing the distribution of states in the data set. Arrows indicate causal relationships in the model.
Figure 4Potential influences of nework variables. Potential influence of network variables on a water source being functional, P(Functionality) = Yes, from least sensitive variables at the top to most sensitive at the bottom. The width of bars indicates the influence of each variable on the likelihood of functionality being in the “Yes” state.
Selected Descriptive Statistics for Sources in Study Area
| Factor |
| |
|---|---|---|
| Waterpoint functional | No | 283 (20.6) |
| Yes | 1089 (79.4) | |
| Borehole functional | No | 245 (20.3) |
| Yes | 961 (79.7) | |
| Other improved source functional | No | 38 (23.2) |
| Yes | 126 (76.8) | |
| Breakdowns in the past year | No | 751 (54.7) |
| Yes | 621 (45.3) | |
| Number of breakdowns in the past year | 0 | 751 (54.7) |
| 1 | 288 (21) | |
| 2+ | 333 (24.3) | |
| Waterpoint rehabilitation | No | 938 (68.4) |
| Yes | 434 (31.6) | |
| Source type | Borehole with handpump | 1206 (82.2) |
| Other improved source | 164 (11.2) | |
| Unimproved | 98 (6.7) | |
| Pump type | Afridev | 256 (19.1) |
| India Mark II | 868 (64.7) | |
| Nira | 45 (3.4) | |
| Vergnet | 9 (0.7) | |
| No pump | 164 (12.2) | |
| Age of waterpoint | <5 years | 154 (11.7) |
| 5–10 years | 158 (12.1) | |
| 10–15 years | 460 (35.1) | |
| 15–20 years | 359 (27.4) | |
| 20+ years | 180 (13.7) | |
| Constructing organization | Bank/company/individual | 23 (1.7) |
| Community/district assembly | 100 (7.6) | |
| Development bank/Foreign government | 101 (7.7) | |
| Do not know | 121 (9.2) | |
| Hilton | 898 (68.1) | |
| Non‐hilton funded NGO/church | 75 (5.7) | |
| Waterpoints enumerated in the community | 1 waterpoint | 217 (14.8) |
| 2–3 waterpoints | 566 (38.5) | |
| 4–6 waterpoints | 313 (21.3) | |
| 7+ waterpoints | 374 (25.4) | |
| Identified management within the community | Identified management in community | 1228 (90) |
| No identified management in community | 137 (10) | |
| Interviewee's knowledge of number of users | No | 864 (63) |
| Yes | 508 (37) | |
| Number of users (quartiles) | 0–20 | 145 (28.5) |
| 150+ | 134 (26.4) | |
| 21–49 | 81 (15.9) | |
| 50–150 | 148 (29.1) | |
| Tariff collected | No | 713 (52) |
| Yes | 659 (48) | |
| Time of tariff collection | Paid per unit time (daily, weekly, monthly, yearly) | 224 (34.4) |
| Per trip/bucket | 418 (64.2) | |
| When broken down, occasionally | 9 (1.4) | |
| Savings (cedis) | 0–10 | 366 (41.8) |
| 10–100 | 373 (42.6) | |
| 100–1000 | 136 (15.5) | |
| Time needed to get spare parts | 0 days | 126 (11.2) |
| 1–6 days | 667 (59.5) | |
| >1 week | 328 (29.3) | |
| Time needed for a mechanic | 0 days | 118 (10.7) |
| 1–2 days | 711 (64.2) | |
| 3+ days | 278 (25.1) | |
| Interviewee's awareness of an area mechanic | No | 332 (32) |
| Yes | 707 (68) | |
| Population density quartiles (Population per 100 m2) | Q1: < 0.1055 people per 100 m2 | 376 (25.6) |
| Q2: 0.1058–0.4071 people per 100 m2 | 372 (25.3) | |
| Q2: 0.4104–5.5724 people per 100 m2 | 370 (25.2) | |
| Q3: 5.6142–285 people per 100 m2 | 352 (23.9) | |
| Groundwater storage (water depth in mm) | L: <1000 mm | 370 (25.2) |
| LM: 1000–10,000 mm | 109 (7.4) | |
| M: 10,000–25,000 mm | 991 (67.4) | |
| Groundwater productivity (boreholes—L/s) | L: 0.1–0.5 L/s | 305 (21.2) |
| LM: 0.5–1 L/s | 779 (54.2) | |
| M: 1–5 L/s | 236 (16.4) | |
| VL: <0.1 L/s | 118 (8.2) | |
| Depth to groundwater (meters belowground) | S: 7–25 m below ground | 1004 (68.3) |
| VS: 0–7 m below ground | 466 (31.7) | |
| Distance to town of at least 10,000 people | 0–12 km | 359 (24.4) |
| 12–22 km | 359 (24.4) | |
| 22–48 km | 388 (26.4) | |
| 48–82 km | 364 (24.8) | |
| District | Ashanti Akim | 269 (19.6) |
| Atebubu | 97 (7.1) | |
| Ejura Sekyedumasi | 167 (12.2) | |
| Kwahu East | 82 (6) | |
| Kwahu North | 157 (11.4) | |
| Kwahu South | 95 (6.9) | |
| Kwahu West | 67 (4.9) | |
| Mampong Municipal | 27 (2) | |
| Pru | 86 (6.3) | |
| Sekyere Afram Plains | 30 (2.2) | |
| Sekyere Central | 86 (6.3) | |
| Sekyre East | 65 (4.7) | |
| Sene | 144 (10.5) | |
| Water sources per community | Median | 2 |
| Community has ≥1 functional improved source | Yes | 507 (94.4) |
| No | 30 (5.6) |
Univariable Logistic Regression Results for All Sources
| Contrast | OR | 95% CI |
|
|---|---|---|---|
| Failure in the past year: yes versus no | 0.4 | (0.3–0.6) | <0.0001 |
| Rehabilitation: yes versus no | 1.4 | (1–2) | 0.0236 |
| Source type: borehole with handpump versus other improved source | 1.3 | (0.9–2) | 0.2435 |
| Pump type: Afridev versus India Mark II | 1.6 | (1.1–2.4) | 0.0742 |
| Pump type: Nira versus India Mark II | 1.1 | (0.5–2.3) | |
| Pump type: Vergnet versus India Mark II | 0.5 | (0.1–2.5) | |
| Pump type: not a borehole versus India Mark II | 0.9 | (0.6–1.3) | |
| Pump type: India Mark II versus all other pump types | 0.7 | (0.5–1) | 0.0534 |
| System age: <5 years versus 20+ years | 0.8 | (0.5–1.3) | 0.0289 |
| System age: 5–10 years versus 20+ years | 0.6 | (0.4–1) | |
| System age: 10–15 years versus 20+ years | 0.5 | (0.3–0.8) | |
| System age: 15–20 years versus 20+ years | 1.1 | (0.6–2.1) | |
| Constructing organization: Hilton versus Other | 1.2 | (0.9–1.7) | 0.2189 |
| Waterpoints enumerated in the community: 1 versus 7+ | 2.9 | (1.5–5.3) | <0.0001 |
| Waterpoints enumerated in the community: 2‐3 versus 7+ | 0.9 | (0.6–1.4) | |
| Waterpoints enumerated in the community: 4‐6 versus 7+ | 1 | (0.6–1.7) | |
| Identified management in the community: Yes versus No | 2.3 | (1.5–3.4) | 0.002 |
| Interviewee's knowledge of number of waterpoint users: yes versus no | 2.1 | (1.5–2.9) | <0.0001 |
| Number of users: 0–20 versus 150+ | 0.9 | (0.5–1.8) | 0.0072 |
| Number of users: 21–49 versus 150+ | 3.6 | (1.2–10.2) | |
| Number of users: 50‐149 versus 150+ | 1.4 | (0.7–2.8) | |
| Tariff collected: yes versus no | 1.7 | (1.2–2.4) | 0.0022 |
| Daily, weekly, monthly, yearly | 1.3 | (0.7–2.1) | 0.3828 |
| When broken down, occasionally versus per trip/bucket | 0.4 | (0.1–1.8) | |
| Savings: 0–10 Cedis versus 100–1000 cedis | 1 | (0.7–1.6) | 0.9756 |
| Savings: 10–100 Cedis versus 100–1000 cedis | 1.1 | (0.6–2) | |
| Time needed to get spare parts: 0 days versus 1–6 days | 0.8 | (0.5–1.5) | 0.1978 |
| Time needed to get spare parts: 0 days versus >1 week | 1.3 | (0.9–1.8) | |
| Time needed for a mechanic: 0 versus 3+ | 1.2 | (0.7–2.2) | 0.0147 |
| Time needed for a mechanic: 1–2 versus 3+ | 1.8 | (1.3–2.7) | |
| Awareness of an area mechanic: yes versus no | 1.3 | (0.9–2) | 0.1817 |
| Population density increase by 5 people per 100 m2 | 1 | (1–1) | 0.2942 |
| Groundwater storage: L (<1000 mm) versus M (10,000–25,000 mm) | 1.6 | (1.1–2.2) | 0.0182 |
| Groundwater storage: LM (1000–10,000 mm) versus M (10,000–25,000 mm) | 1.5 | (0.9–2.6) | |
| Borehole productivity: L (0.1–0.5 L/s) versus VL (<0.1 L/s) | 0.7 | (0.4–1.3) | 0.2413 |
| Borehole productivity: LM (0.5–1 L/s) versus VL (<0.1 L/s) | 1.1 | (0.7–1.9) | |
| Borehole productivity: M (1–5 L/s) versus VL (<0.1 L/s) | 0.8 | (0.4–1.5) | |
| Depth to groundwater: 7–25 m versus 0–7 m below ground | 1 | (0.7–1.3) | 0.8909 |
| Distance: 12–22 km versus 0–12 km | 0.9 | (0.6–1.4) | 0.0927 |
| Distance: 22–48 km versus 0–12 km | 0.6 | (0.4–0.9) | |
| Distance: 48–82 km versus 0–12 km | 0.7 | (0.4–1.1) | |
| District: Ashanti Akim versus Ejura Sekyedumasi | 1.8 | (1–3.3) | 0.0011 |
| District: Atebubu versus Ejura Sekyedumasi | 0.8 | (0.4–1.7) | |
| District: Kwahu East versus Ejura Sekyedumasi | 0.6 | (0.3–1.2) | |
| District: Kwahu North versus Ejura Sekyedumasi | 0.8 | (0.4–1.6) | |
| District: Kwahu South versus Ejura Sekyedumasi | 0.5 | (0.3–0.9) | |
| District: Kwahu West versus Ejura Sekyedumasi | 0.5 | (0.3–0.9) | |
| District: Mampong Municipal versus Ejura Sekyedumasi | 0.9 | (0.4–1.7) | |
| District: Pru versus Ejura Sekyedumasi | 1 | (0.4–2.4) | |
| District: Sekyere Afram Plains versus Ejura Sekyedumasi | 0.7 | (0.3–1.3) | |
| District: Sekyere Central versus Ejura Sekyedumasi | 3.1 | (0.7–13) | |
| District: Sekyre East versus Ejura Sekyedumasi | 0.5 | (0.2–0.9) | |
| District: Sene versus Ejura Sekyedumasi | 1.1 | (0.5–2.2) |
Multivariable Logistic Regression Model for Water Source Functionality
| Contrast | OR | 95% CI |
|
|---|---|---|---|
| Failure in the past year: yes versus no | 0.4 | (0.3–0.6) | <0.0001 |
| Pump type: Afridev versus India Mark II | 1.2 | (0.7–1.9) | 0.9336 |
| Pump type: Nira versus India Mark II | 1.2 | (0.5–2.6) | |
| Pump type: Vergnet versus India Mark II | 1.2 | (0.7–2) | |
| system age: <5 years versus 20+ years | 1 | (0.5–1.9) | 0.1209 |
| system age: 5–10 years versus 20+ years | 0.8 | (0.4–1.5) | |
| system age: 10–15 years versus 20+ years | 0.6 | (0.3–1.2) | |
| system age: 15–20 years versus 20+ years | 1.5 | (0.8–3) | |
| Number of waterpoints: 1 versus 7+ | 4.8 | (2.3–10.1) | <0.0001 |
| Number of waterpoints: 2–3 versus 7+ | 1.6 | (1–2.6) | |
| Number of waterpoints: 4–6 versus 7+ | 1.5 | (0.9–2.5) | |
| Constructing organization: Hilton versus Other | 1.5 | (0.9–2.3) | 0.1079 |
| Identified management in the community | 1.6 | (1–2.7) | 0.0918 |
| Tariff: yes versus no | 1.9 | (1.2–3.1) | 0.0105 |
| Groundwater storage: L (<1000 mm) versus M (10,000–25,000 mm) | 2.9 | (1.4–5.9) | 0.0219 |
| Groundwater storage: LM (1000–10,000 mm) versus M (10,000–25,000 mm) | 2.2 | (0.9–5) | |
| Borehole productivity: L (0.1–0.5 L/s) versus VL (<0.1 L/s) | 0.5 | (0.2–1.3) | 0.2984 |
| Borehole productivity: LM (0.5–1 L/s) versus VL (<0.1 L/s) | 0.9 | (0.4–2.3) | |
| Borehole productivity: M (1–5 L/s) versus VL (<0.1 L/s) | 0.6 | (0.3–1.2) | |
| Depth to groundwater: 7–25 m versus 0–7 m below ground | 1.3 | (0.9–2) | 0.1594 |
| Distance: 12–22 km versus 0–12 km | 1.5 | (0.8–2.9) | 0.4673 |
| Distance: 22–48 km versus 0–12 km | 1.1 | (0.5–2.4) | |
| District: Ashanti Akim versus Ejura Sekyedumasi | 1.2 | (0.4–3) | 0.0062 |
| District: Atebubu versus Ejura Sekyedumasi | 1.6 | (0.5–4.8) | |
| District: Kwahu East versus Ejura Sekyedumasi | 0.4 | (0.1–0.9) | |
| District: Kwahu North versus Ejura Sekyedumasi | 1.6 | (0.6–4.5) | |
| District: Kwahu South versus Ejura Sekyedumasi | 0.2 | (0.1–0.7) | |
| District: Kwahu West versus Ejura Sekyedumasi | 0.2 | (0.1–0.7) | |
| District: Mampong Municipal versus Ejura Sekyedumasi | 0.2 | (0.1–0.7) | |
| District: Pru versus Ejura Sekyedumasi | 0.7 | (0.2–3.2) | |
| District: Sekyere Afram Plains versus Ejura Sekyedumasi | 1 | (0.4–2.8) | |
| District: Sekyere Central versus Ejura Sekyedumasi | 3.3 | (0.6–18.3) | |
| District: Sekyre East versus Ejura Sekyedumasi | 0.6 | (0.3–1.3) | |
| District: Sene versus Ejura Sekyedumasi | 0.4 | (0.1–1.5) |
Bayesian Network Model for Water Source Functionality
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Variables that were significant in the multivariable logistic regression.