Transcript

Water is chemically safe and clean, making

microbial hazards the primary concern

Present systems have a good design and are capable

of delivering disinfected water

Optimal system management requires well trained

chlorine testers, regular monitoring, and thorough

record keeping

Community feedback and flavor can have strong

influence on chlorine dosing in the absence of

comprehensive system management techniques

Community education is vital to the success of a

community led water system

World Health Organization, ed. 2004 Guidelines for Drinking-

Water Quality, 3rd edn. Geneva.

http://geology.com/world/south-america-physical-map.shtml

https://www.ezilon.com/maps/south-america/ecuador-physical-

maps.html

Introduction Methods Results

Conclusions

References

Analyze efficacy of the piped, chlorine disinfection

and distribution systems in each community based on

free residual chlorine concentrations

Chlorine potency is influenced by a variety of factors

including concentration, temperature, contact time,

and most significantly pH

Analyze physicochemical hazards and factors effecting

disinfection and palatability

Assess microbial hazards as well as system

management and community feedback

Perform community taste tests to determine how

chlorine concentration impacts palatability of the

drinking water

(above) rural community and landscape (below)

testing a rural water system in a community

Physicochemical Analysis

Clean Water in EcuadorKurtis Duff, Dr. Chad Tatko, Calvin College, Grand Rapids, Michigan

Community

SiteEC TDS Temperature pH Color Turbidity Nitrite Nitrate Sulfate Iron Phosphate Magnesium Calcium CO2 Cl-

1 472 234 16.0 8.15 17 0 0.007 0.98 0 0.09 4.28 --- --- 48.2 1.7

2 107 54 10.4 8.64 0 0 0 0 2.67 0.05 2.70 2.31 +++ 69 1.4

3 122 59 13.0 7.82 0 0 0 0 1.67 0 0.76 3.55 +++ 48.6 1.7

4 523 260 15.6 8.40 0 0 0 +++ 0 0 0 0 0 25.2 9

5 361 180 13.9 8.27 --- --- --- --- 10 0.06 0.01 0.87 0.34 50 2.3

6 122 63 12.0 8.21 0 0 0.015 0.09 0 0.04 0.74 +++ 3.26 47.6 1.6

7 834 416 17.2 8.16 0 0 0.089 0.17 42 0.08 1.57 0.25 0.62 --- ---

8 535 265 16.6 8.20 0 0 --- --- 74 0.04 0.12 1.43 0 --- 11

9 521 261 18.5 7.70 0 0 --- --- 10 0.04 0.53 1.36 0 88 2.1

10 521 263 19.3 8.00 0 0 0.027 0.07 10 0 0.33 0.68 0 68 1.1

11 695 341 13.1 7.86 0 0 0.012 0.06 37 0.09 0.02 0.42 0.19 64 4.3

12 516 258 17.1 8.17 0 0 0 0 +++ 0 0.72 2.25 3.92 --- ---

13 283 144 13.00 8.34 0 0 --- --- 3 0.03 0.07 2.01 0 81 16.4

14 172 350 14.8 8.35 0 0 0 0.07 0 0.04 +++ 1.38 2.77 40.4 1.5

15 324 162 15.1 7.43 0 0 0.021 0.47 1 0.13 +++ 2.31 3.89 50 1.2

16 625 311 13.4 7.75 0 0 0 0 24 0 1.32 0.99 0.86 --- ---

17 653 312 13.5 8.06 0 0 0 0 23 0 1.78 1.88 3.06 --- ---

18 485 242 16.0 7.80 0 0 0.004 +++ 12 0.05 0.07 1.61 0 84 1.2

USGS

Standards250-750 500 N/A 6.5 - 8.5 15 5 1 10 250 0.30 N/A 61 61 N/A 250

In country field tests and IC analysis both show that

source groundwater is clean (within USGS guideline

values and similar to Calvin tap water chemically)

Tests for bacteria reveal variable concentration of

combined coliforms and fecal coliforms, depending on

community, but consistently above recommended values

Access to safe drinking water is

one of the greatest barriers to

achieving global public health

Hazards present in drinking water

supplies vary greatly depending

on the system

In 2004, the World Health

Organization (WHO) introduced

Water Safety Plans (WSPs),

which are comprehensive risk

assessment and management

plans developed for systems

individually

Water system management and disinfection are

particularly important in developing countries such

as Ecuador, where 36% of population is made up

of small, rural communities and microbial hazards

are a greater risk

Chemical disinfection, using chlorine, is the most

efficient for treating hazards because it both

disinfects and remains in the system to protect it

Visited/ studied 19 rural communities in the

Chimborazo province of Ecuador, located in the

Andean mountain valley

Community led water systems providing

water to 50 – 375 household taps

Chlorine tests consistently show that free residual

chlorine concentrations are insufficient both at the

source and POU

Observed that stocks for initial dosing are made

incorrectly, no form of record keeping present,

verbal feedback about flavor from community

members influenced dosing

Tested Source Poor Range Moderate Range Good Range

Source Water 0 - 0.2 ppm 0.2 - 0.5 ppm 0.5 - 1.0 ppm

POU 0 - 0.15 ppm 0.15 - 0.3 ppm 0.3 - 0.5 ppm

61.5%

15.4%

23.1%

75.0%

18.8%

6.3%

69.0%

17.2%

13.8%

0.0%

10.0%

20.0%

30.0%

40.0%

50.0%

60.0%

70.0%

80.0%

90.0%

100.0%

Poor Moderate Good

Source Water POU Total

Chlorine Residual Analysis

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