examining the potential of using spring waters for domestic and irrigation farming activities: case...

EXAMINING THE POTENTIAL OF USING SPRING WATERS FOR DOMESTIC AND IRRIGATION FARMING ACTIVITIES:

CASE STUDY OF LIWONDE, MALAWI.

A Russel C.G. Chidya (MSc)Prof Wapulumuka O. MulwafuAss Prof Samson S.M.I Sajidu

A Corresponding author: E-mail: [email protected]

University of Malawi – Chancellor College

Date: 31st Oct – 2nd Nov 2012

13th WaterNet/WARSFSA/GWP-SA International Symposium on IWRM 1

NEPAD SANWATCEwww.nepadwatercoe.org

AMCOW

Presentation Outline

2NEPAD SANWATCEwww.nepadwatercoe.org

1. Introduction & Literature Review

2. Aim and Objectives

3. Methods and Materials

4. Results & Discussion

5. Conclusion & Recommendations

6. Acknowledgements

1. Introduction & Literature review


Water is a finite natural resource essential for the well being of mankind (GWP, 2010).Important water sources:

a. surface water i.e. springs, streams and rivers ponds, lakes &seas.

b. ground water i.e.: located in aquifers – related to wells, boreholes &springs

In Malawi, existence of rivers, springs, L. Malawi, L. Chilwa and other smaller lakes provide fresh water resources.

However, climate variability, poor agricultural practices, poor waste disposal, poor water use and poor management of catchment areas etc pose daunting challenges which could result in quality & access to water resources being strained in the near future (Kass et al, 2005; GWP, 2010).

Intr‘d cont.../...


Springs are an important source of water for various purposes i.e. domestic, irrigation, & fishing (Spechler &Schiffer, 1995; WHO, 2008).

Previous studies by UNEP & GPF showed that Liwonde is one the areas in Malawi that have both hot and cold spring water sources.

However, there is no established data on the exact location & capacity of these springs. No attempt has been made to assess the socio-economic use, management & governance systems of these springs.

Further, no data is available on the physico-chemical characteristics of the spring waters and their implications for domestic and irrigation use.

2. Aim & specific objectives


Main Aim:To examine the potential of using cold and hot spring waters for domestic and irrigation farming activities in Liwonde, Malawi.

Specific Objectives

1. To assess the socio-economic use and governance systems of spring water resources.

2. To study the physico-chemical characteristics of spring water resources and their implications for domestic and irrigation use.

3. To examine the water discharge and capacity of springs to support large-scale domestic and irrigational farming activities.

3. Methods & Materials

6

3.1 Description of the study area – Liwonde

Situated in Southern Malawi & lies at 470 – 531 m above sea level. experiences tropical climate, &receives a relatively low rainfall. Is one of the hottest areas (mean max T of 39 °C). Lies in Shire R plain & is partly surrounded by Mts.

Fig 1A: Map of Africa & Malawi showing location of Study Area

SW1

N

SW10

Liwonde Township

To Lilongwe

From Blantyre

SW2

SW3

SW4

SW11

SW12

SW5

SW6

SW7SW8

SW9SHIRE RIVER

Mts

Fig 1B: Location of sampling sites


13 Hot & cold springs were identified, most connected to boreholes.

3.2 Water sample collection

BoreholeSpring water flow thru borehole

Aquifer system

Fig 2: Schematic diagram of a borehole connected to a spring

Water samples collected in triplicate using 0.5 L cleaned plastic bottles; transported &preserved in accordance with std methods (APHA, 1998; WII, 2008).

Fig 3: A hot spring in Liwonde

3.3 Physico-chemical & discharge analyses


Table 1: Water Quality parameters & analytical methods used

Parameter Site MethodpH, water T, EC, & TDS On site Field digital meters

Alkalinity, (as CO32- &HCO3

- ) LAB Titration (WII, 2008)

Total hardness (due to Ca2+ & Mg2+) LAB EDTA titrimetric (APHA, 1998; WHO, 1999).

Cl- LAB ISE method (APHA, 1998; NICO, 2000)

SO42- LAB Turbidmetric (UV/Vis spectrophotometer, model #. 6405,

England )

PO43- LAB Vanadomolybdophosphoric acid Colorimetric

(UV/Vis, model #. 6405, England)

Ca, Mg, K, Na, Cd, Zn, Cu, & Mn LAB AES (Agilent 4100 MP-AES, USA)

Discharge of springs flowing through boreholes

On-site Volumetric method with a bucket at an average height of about 70 cm.


3.4 Irrigational water quality indices

100)22(

)(%

KNaMgCa

KNaNa

100)22(

)2(MHR

MgCa

Mg

223

23 MgCaHCOCORSC

2221 MgCa

NaSAR

The following equations were used to determine: SAR, %Na, MHR, & RSC (Bauder et al., 2008):

- - - - - - - - - - [1]

- - - - - - - - - - [2]

- - - - - - - - - - [3]

- - - - - - - - - - [4]

3.5 Socio-economic data collection


The socio-economic activities making use of springs in the study area investigated thru:

Field visits, Observations, key informant interviews literature review

3.6 Statistical AnalysisSocial-economic data evaluated by repeated reading &content analysis. Water quality &discharge data analysed by Microsoft Excel (Windows 2007) to compute means, standard deviations & Pearson Correlation C (2-tailed at 95%)

4. Results & Discussion


Fig 4 (A, B, C): Pictures showing spring flow through boreholes in Liwonde. (Photos: Russel Chidya)

4.1 The socio-economic activities and spring water management 12 cold & hot springs identified & most (75%, n=12) were associated with boreholes.

A

B

C

Results & Discussion cont‘d

12

Preliminary results revealed that spring waters in the area are used for:

1. domestic purposes. i.e. washing, bathing, cooking & drinking.

2. small-scale subsistence &commercial farming (vegetables, rice, sugarcane, & maize).

3. moulding of bricks, 4. fish ponds

Fig 5: Pictures showing multiple uses of spring waters. (Photos: Russel Chidya)

NEPAD SANWATCE 13

Watering of nursery & tree seedlings

Growing of vegetables

Fig 6: Photos showing multiple use of springs waters. (photos: R Chidya)

Results & Discussion cont‘d


Major problems observed

Congestion (>300 households)Poor management

Lack of maintenance

Poor Sanitation (photo by Russel Chidya)

ANY POSSIBLE INTERVENTION?

Integrated approach in spring water usage and management, hence IWRM i.e. to address:

oHygiene & SanitationoWater quality & quantityoAccess to water

4.2 Physico-chemical characteristics


SW1

SW2

SW3

SW4

SW5

SW6

SW7

SW8

SW9

SW10

SW11

SW12

0

2

4

6

8

10

12

14 pH

Sampling point

pH

WHO limit (6.5 – 8.5)

Spring waters slightly basic; pH range 7.7 – 9.1

Most sites (67%, n=12) registered pH > upper WHO (2008) limit, hence deemed not suitable for consumption

0100200300400500600700800900

1000 EC (range 555 - 948 uS/cm)

Sampling point

EC

Both EC &TDS were within MBS (2005) limit (EC 700 – 1500 (µS/cm).

However, springs near Shire R showed slightly higher EC & TDS, hence depict high ionisation and dissolution of minerals.

4.2 Physico-chemical characteristics ... cont’d


Site Turbidity (FNU)

T (ºC) Discharge (cm3/s)

CO32-

(mg/L)

HCO3-

(mg/L)

SO42-

(mg/L)

PO43-

(mg/L)

Cl-

(mg/L)

SW1 0.18 27.73 296.88 13.8 329.22 32.36 bdl 72.44SW2 0.13 29.00 309.33 14.32 225.58 36.85 bdl 117.35SW3 0.14 28.33 824.08 16.88 250.04 32.93 0.33 191.36SW4 0.09 27.00 296.88 12.36 332.98 26.09 bdl 135.48SW5 0.12 28.47 433.94 48.04 165.15 33.88 bdl 103.40SW6 1.06 38.00 Nd 42.8 175.60 25.92 0.33 105.87SW7 0.25 26.40 134.12 41.24 177.06 39.62 0.67 129.56SW8 1.30 30.33 Nd 42.76 172.91 37.72 1.17 120.92SW9 0.26 25.80 29.41 26.28 180.15 32.61 bdl 77.99

SW10 0.24 39.70 Nd 25.44 151.85 115.80 bdl 19.52SW11 12.83 41.33 Nd 27.12 145.00 84.95 1.67 62.08SW12 10.58 40.33 Nd 26.68 146.89 88.91 1.17 112.41MBS

(2005)≤5.0 NA NA NA NA 200-

400NA 100-200

WHO (2008)

0.1-1.0 NA NA NA NA 500* NA 250

T: water temperature. Nd: not determined. bdl: below detection level. MBS: Malawi Bureau of standards. WHO: World Health Organisation. NA: not available. Nh: not of health concern at levels found in drinking water. *taste threshold value

Table 2: Results on physico-chemical characteristics of the spring water

Results & Discussion – cont‘d


Based on WHO (2008) hardness classification, all samples registered ‘soft class’ (0-70 mg/L CaCO3).

SO42-, Cl-, Mg, Ca, Na, Cu, & Mn were below WHO (2008) limits at all sites,

hence water generally safe for domestic use. However, due to presence of Cd & relatively high levels of Na at some sites, further water quality studies needed to justify this claim.

Suitability of water for irrigation: Based on SAR, 4 sites fell under excellent ‘S1 class’ (0-10); 2 sites registered

‘good’ (SAR 10-18), 1 site doubtful (SAR 18-26) and 5 sites ‘unsuitable classes’ (SAR>26).

But, based on RSC & %Na by Bauder et al., (2008) all sites were unsuitable for irrigation due to elevated CO3

2-, HCO3- and Na+ ions that tend to affect

irrigable soil properties.

This study has shown that the springs have both socio-economic value and capacity to support large-scale farming & domestic use.

However, major challenges faced include poor sanitation, governance & management systems. Further, water quality analyses indicated that some springs are of poor quality.

RECOMMENDATIONS & FURTHER STUDIES

Integrated approaches (i.e. IWRM) are needed for sustainable use, governance &proper management of the springs.

Further studies are needed on hydrology and aquifer systems of the area, microbiological tests & human health; & soil analysis for sustainable farming.

5. Conclusion


6. Acknowledgements


Authors would like to express their sincerely gratitude to the following:

NEPAD SANWATCE– for sponsorship towards the student’s expenses to attend the conference.

SADC WaterNet-Malawi Chapter for partially sponsoring the research study.

13th WaterNet/WARFSA/GWP-SA Secretariat for accepting our abstract & manuscript

Department of Chemistry – Chancellor College (University of Malawi) – for provision of lab space

THE ENDTHANK YOU!!

ZIKOMO


“Let there be work, bread, water & salt for

all”-Nelson Mandela-

(Adapted from: Water, Energy & Development 2012 by ESKOM)

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