Tag: Handpump Failure

The role of galvanized pipes in the corrosion and failure of hand pumps

Stop the Rot during ZAWAFE 2023 Zambia – 4/4

This blog is part of a four-part series covering the presentations given at the 11th Zambia Water Forum and Exhibition. The event, themed “Accelerating Water Security and Sanitation Investments in Zambia: Towards Agenda 2023 through the Zambia Water Investment Programme”, lasted three days. 

Our blog series takes a focused look at the presentations and discussions that revolved around “Addressing Rapid Hand Pump Corrosion in Zambia – Stop the Rot!”, which was co-convened by UNICEF and WaterAid,  together with Ask for Water GmbH and the RWSN, hosted by Skat Foundation. 

Cover photo: Red, iron-rich water being pumped. Photo: WaterAid Uganda

Second session:

The role of galvanized pipes in the corrosion and failure of hand pumps

Empowered Communities Helping Others (ECHO) has been implementing a safe water project since 2020. This is a Water Sanitation and Hygiene (WASH) project, whose main intervention is borehole rehabilitation which is implemented in rural parts of Zambia’s Western and Central Provinces, in collaboration with the Local Authority. In practice, the need to rehabilitate a borehole arises when a functioning borehole presents usage problems such as non-production of water, worn out parts such as pipes, rods, handles, chains, cylinders, water chambers, pedestal, head assembly, bearings, etc.

Since 2020, ECHO has rehabilitated a total of about 850 boreholes in Central and Western Zambia, benefiting a total of about 255,000 people. 

It was found that rehabilitating a borehole can be more economical than constructing a new one. It is simpler and faster and can be an appropriate solution in an emergency because it doesn’t require things like mobilizing a drilling rig. However, if the rehabilitated borehole is to be used for a long time, it is important to estimate its life expectancy.

The rehabilitation option chosen depends on the conditions of the existing borehole, the causes of the damage, the technical and logistic options, and the existing alternatives such as the construction of a new water point. 

According to the severity of the borehole problems, the work requirements may vary from a simple repair at the surface to re-equipment. 

For the project, all GI pipes are replaced with new PVC ones. This is done in order to prevent and reduce iron contamination (as a result of corrosion) which from the past four years we have observed is a contributing factor to borehole failure and abandonment 

The main observed sources of iron are: 

▪ From natural sources in the aquifer 

▪ From pump components such as steel casings and galvanized pipes. 

▪ In other instances, a combination of both has been observed to be possible. ▪ Within 3 to 6 months of installing hand pumps with galvanized material, pipes and rods have been found to be heavily corroded. 

▪ When corrosion is the main source of iron, iron concentrations reduce drastically when water is pumped out and fresh recharge is allowed. If iron concentrations remain high throughout during continued pumping, the case has been that it is likely the iron is coming from the aquifer.

Experiences on hand pump corrosion 

Hand pumps with GI pipes, sometimes only a year or two old have corroded, and people have returned to unprotected water sources. Water with pH below 6 has been observed to have corroded pipes. High iron concentrations in handpumps have been a usual occurrence this has been observed through regular water quality testing and evaluating the change in iron concentration over the period of our operations. Stainless steel pipes and rods had corrosion rates lower than galvanized iron (GI) pipes and rods.

Experiences on hand pump corrosion 

The brown or reddish color is observed in the morning when the pumps had not been used during the night 

However, groundwater has been observed to hold significant concentrations of iron but appears clear and colorless. When this water is pumped out after being exposed to the atmosphere, the color changes to red/brown.

Figure 3: Sampled on Friday 2nd June 2023 in Central Province. 

General complaints recorded from communities: 

Within weeks and months of installation, communities would begin to complain about water quality. These complaints range from metallic taste, odor, and the appearance of water. Also, the communities would report discoloration of water and cloths and highly turbid water. 

All these result in people abandoning the water point and going back to unprotected alternative water sources. 

Positive observations 

The use of uPVC pipes and stainless-steel adapters has so far shown positive results in reducing iron contamination.  After switching from galvanized pipes to UPVC, the communities have observed reduced to no brown or reddish color in the water.  uPVC pipes last long, so you won’t have to worry about replacing them anytime soon. Since uPVC is non-porous, uPVC pipes help by preventing any contamination from occurring. uPVC is resistant to corrosion as it is not susceptible to chemical and electrochemical reactions, so there are better option in controlling iron contamination. The use of uPVC pipes and stainless-steel adapters has so far shown positive results in reducing iron contamination

Figure 4:  Riser pipe removal and water quality testing for an installation that was less than six months old by ECHO. 

What we are advocating for: 

▪ Stakeholders should address the handpumps with corrosion problems as a priority in order to guarantee the water quality we supply to the people.

▪ Testing boreholes that present iron contamination to determine whether the source of iron is from the aquifer or from corrosion. This will provide the best options for the right material to equip the water point with 

▪ Competent borehole drilling and rehabilitation supervision should be ensured so that all standards and specifications are adhered to. 

▪ Regular water quality analysis is undertaken, and critical parameters are tested to address problems such as corrosion and other related problems that shorten the life span of a hand pump

You are invited to access the presentations HERE, along with the session’s concept and report. If you would like to dive deeper into the enriching exploration of water challenges and solutions through the Stop the Rot initiative, visit this page.

About the author: 

Annie Kalusa – Kapambwe presenting at  at ZAWAFE 2023 

Annie Kalusa is an accomplished development practitioner and administrator. Currently working for a local Zambian NGO Empowered Communities Helping Others (ECHO) in Zambia, focusing on improving the wellbeing of Vulnerable Rural Communities. Her areas of focus are climate resilient Water Sanitation and Hygiene (WASH). She is currently developing her thesis on Rural Agriculture Practices and Mechanisms for Water Resource Management.

Photo credits: Annie Kalusa

The journey towards reducing the effects of rapid corrosion in Kalumbila District, Zambia

Stop the Rot during ZAWAFE 2023 Zambia – 3/4

This blog is part of a four-part blog series highlighting the presentations delivered during the 11th Zambia Water Forum and Exhibition.  The event, themed “Accelerating Water Security and Sanitation Investments in Zambia: Towards Agenda 2023 through the Zambia Water Investment Programme”, lasted three days. 

Our blog series takes a focused look at the presentations and discussions that revolved around “Addressing Rapid Hand Pump Corrosion in Zambia – Stop the Rot!”, which was co-convened by UNICEF and WaterAid,  together with Ask for Water GmbH and the RWSN, hosted by Skat Foundation. 

Third session:

The journey towards reducing the effects of rapid corrosion in Kalumbila District.

Kalumbila District is a district in the North-Western Province of Zambia. It has two major mines namely Lumwana and Kalumbila Mines.

With a population of over 170,000, the district has about 300 water points (boreholes and protected wells equipped with handpumps). 

Rapid handpump corrosion has been a problem since the district was created in 2015. One of the interventions that the district has undertaken has been iron removal filters (to remove iron from pumped water), although these have not been sustainable. 

Figure 1: Location of Kalimbula District

In every program of drilling of boreholes about 40% of boreholes were abandoned within one year after handover due to rapid corrosion.

We started looking for a solution to this problem. We found that iron filters were used but were not sustainable. 

Figure 2: Handpump evaluation

One of the interventions that the district has undertaken has been iron removal filters (to remove iron from pumped water), although these have not been sustainable. In Kalumbila District it was found, that in every borehole programme, about 40% of the handpumps installed were abandoned due to high iron content, with some boreholes being abandoned as early as three months after construction and commissioning.

Projects

In 2017 UNICEF supported Kalumbila district in the drilling of 23 boreholes and rehabilitation of 15 water points.  

In 2018 JICA also supported Kalumbila district with rehabilitation of 77 water points using uPVC pipes with stainless steel adapters.  It is from these projects that we learnt a lot of important lessons and made recommendations to the D-WASHE committee.  No water point was abandoned after one year of handover  Kalumbila district decided to suspend the use of galvanised iron (GI) pipes and recommended the use of stainless steel and uPVC pipes for Indian Mark II and Afridev hand pumps. 

Lessons learnt

It is from these two projects that we learnt a lot of lessons, and we told ourselves never to keep quiet. From these two projects, we observed that no water point was abandoned after one year of handover. We saw a solution – why continue to use GI pipes when there was a solution. So we made recommendations to the D-WASHE committee. After this, Kalumbila district decided to suspend the use of galvanised iron (GI) pipes and recommended the use of stainless steel and uPVC pipes for India Mark II and Afridev hand pumps. We have discovered that handpumps with stainless steel riser pipes do not require frequent repair and maintenance whereas sometimes the GI pipes would require replacement every six months. For the past four years, those handpumps remain working. 

Our challenges include a lack of funding for the rehabilitation of boreholes affected by rapid corrosion. Further, some stakeholders have not supported the districts fully. 

Recommendations

  • Stakeholders at the national level take an interest in order to address this issue of rapid corrosion. 
  • The use of materials that are environmentally friendly without change of properties when they come into contact with aggressive water (i.e. materials such as stainless steel and uPVC). 
  • There is capacity building of all Area Pump Menders (APMs) in Afridev hand pumps.
  • All hand pumps that have galvanised iron (GI) riser pipes are to be rehabilitated.

You are invited to access the presentations HERE, along with the session’s concept and report. If you would like to dive deeper into the enriching exploration of water challenges and solutions through the Stop the Rot initiative, visit this page.

About the author:

Daniel Shimanza presenting at ZAWAFE 2023 

Daniel Shimanza is a Zambian Citizen who has worked in the water sector for more than 6 years. He worked on many water supply projects in Kalumbila district, Zambia in collaboration with GRZ, NGOs such as UNICEF, and World Vision. He has a passion for the improvement of access to clean water supply for people living in rural areas. He’s championing a campaign to reduce the effects of rapid corrosion in Kalumbila district by using alternative materials such as stainless steel pipes, PVC pipes, Iron Filters, and more. He holds a Diploma in Water Engineering from NRDC and currently pursuing a Bachelor of Civil Engineering from the Copperbelt University.

When stainless steel is not stainless steel

Stop the Rot during ZAWAFE 2023 Zambia – 2/4

This blog is part of a four-part series covering the presentations given at the 11th Zambia Water Forum and Exhibition. The event, themed “Accelerating Water Security and Sanitation Investments in Zambia: Towards Agenda 2023 through the Zambia Water Investment Programme”, lasted three days.

Our blog series takes a focused look at the presentations and discussions that revolved around “Addressing Rapid Hand Pump Corrosion in Zambia – Stop the Rot!”, which was co-convened by UNICEF and WaterAid,  together with Ask for Water GmbH and the RWSN, hosted by Skat Foundation.

Continue reading “When stainless steel is not stainless steel”

History of the Rapid Hand pump Corrosion Problems in Zambia and Potential Next Steps

Stop the Rot at ZAWAFE 2023 Zambia – 1/4

This blog is part of a four-part series covering the presentations given at the 11th Zambia Water Forum and Exhibition. The event, themed “Accelerating Water Security and Sanitation Investments in Zambia: Towards Agenda 2023 through the Zambia Water Investment Programme”, lasted three days. 

Our blog series takes a focused look at the presentations and discussions that revolved around “Addressing Rapid Hand Pump Corrosion in Zambia – Stop the Rot!”, which was co-convened by UNICEF and WaterAid,  together with Ask for Water GmbH and the RWSN, hosted by Skat Foundation. 

Cover Photo: Removal of corroding riser pipe in Hoima District, Uganda in 2012 (source: Larry Bentley). In 2018 the Government of Uganda issued a directive to prevent further use of galvanised iron riser pipes throughout the country.

First session:

History of the Rapid Hand Pump Corrosion Problems in Zambia and Potential Next Steps

In Sub-Saharan Africa (SSA), an estimated 200 million people rely on a handpump for their main source of drinking water. They most likely use about 700,000 handpumps (Danert, 2022). Although the popularity of other technologies is growing, handpumps are likely to remain important in the region for decades to come, particularly in areas that are remote or with low population density. Unfortunately, many handpump services perform poorly or fail prematurely due to technical or installation defects with the borehole or the pump, as well as weaknesses with operation and maintenance or financial constraints. 

In Zambia, it has been estimated that handpumps are the main source of drinking water for 19% of the urban and 32% of the rural population. It is worth to highlight that all metallic components that are submerged in water, or move in and out of water will eventually corrode, and so corrosion must be considered as part of the long-term maintenance of water wells with handpumps (or motorised pumps). 

About rapid handpump corrosion

Rapid handpump corrosion occurs when aggressive groundwater reacts with galvanised iron (GI) riser pipes and rods of a handpump, and the India Mark II in particular. The materials corrode, with the pumped water becoming bitter in taste, with an unpleasant smell and a rusty colour. This not only renders the water unfit for drinking from a user perspective but also considerably reduces the pump lifespan. In Zambia, the main cause of rapid handpump corrosion is contact between groundwater with a pH of less than 6.5 and GI pipes and rods. However, salinity is also a problem in some parts of the country and can result in rapid corrosion too. 

The use of alternative materials to GI, particularly stainless steel (SS) riser pipes and rods and uPVC rider pipes fitted with stainless steel connectors, can prevent rapid handpump corrosion. While rapid handpump corrosion was documented in West Africa in the late 1980’s ((Langenegger, 1989), and actions to prevent it have been taken in some places, the phenomenon still occurs in over 20 countries in sub-Saharan Africa. Zambia, with an estimated 22,000 handpumps in use, serving 32% of the population with their main drinking water supply, is among these countries. 

Figure 1: Soil reaction map (pH) map of Zambia, 2014. (Shitumbanuma et all, 2021)

Figure 2: Zambia’s Agro-Ecological Zones (1987) and the 10 Provinces (Makondo & Thomas, 2020) 

Figure 3: History of efforts in Zambia in relation to rapid handpump corrosion – Overview

In Zambia, while the geographical extent of aggressive water is not fully understood by water sector professionals, it has been documented and explained with respect to soils.  A Soil Survey by the Mount Makulu Research Station from 1990 presents the situation clearly, with extreme soil acidity in the north, and soil acidity in the central parts of the country. Further, in Zambia the traditional Chitemene – ‘slash and burn’ – method of cultivation in the high rainfall region has been used since time immemorial to neutralise low pH in soils in order to cultivate crops. Leaching from these highly acidic soils affects the pH of the groundwater. 

The problem of rapid corrosion in handpumps in Zambia has been known for more than 30 years (Pitcher, 2001) and is well documented, including in the following: 

  • The Central Province Rural Water Supply Project (CPRWSP) (1985 – 1996) – which installed 564 handpumps with stainless steel riser pipes rather than using GI to prevent rapid corrosion. 
  • The North-Western Province Rural Water Supply and Sanitation Project (2004 – 2009) – over 350 handpumps were installed with stainless steel riser pipes, also in response to the same issue. 
  • In Luapula Province under the Japan International Cooperation Agency (JICA)-supported Groundwater Development Project (2007 – 2010), some Afridev handpumps with uPVC riser pipes were installed. The project rehabilitated existing, corroded handpumps which the community had previously abandoned. Replacing the GI pipes with uPVC stopped the iron problem, indicating that in these boreholes, using iron pipes had been the cause of corrosion. Iron removal plants were also installed on some boreholes. 

However, while solutions were implemented at scale in the aforementioned projects in Central and North-Western Provinces, as well as the study in Luapula, the use of GI riser pipes and rods still continued in subsequent projects in the same areas.

Some stepbacks

  • There was a change in the ministry responsible for drilling works. The period 1985 – 1996 saw borehole drilling under the Department of Water Affairs, while the Department of Infrastructure and Support Services under the Ministry of Local Government and Housing took on this role after it had been created in 1995. 
  • National Guidelines for Sustainable Operation and Maintenance of Handpumps in Rural Areas (MLGH, 2007) includes neither aggressive water as a criterion for handpump selection nor the use of stainless steel riser pipes, and so the use of GI pipes in aggressive water as the cause of the ensuing rapid corrosion was in effect further supported. 

Initiatives undertaken in the last 10 years

  • Under the SOMAP 2 project (2012 – 2013), the JICA-supported programme carried out pipe replacement of GI at 20 sites in four provinces (Luapula, Copperbelt, Central and the North Western) whereby GI pipes were removed, the boreholes flushed and then installed with uPVC pipes. The replaced handpumps performed well without the water turning rusty, and the communities continued to draw water from them, whereas previously they had been abandoned. 
  • UNICEF also carried out pipe replacement in Mansa and Milenge districts of Luapula Province. In the study, India Mark II handpumps GI pipes at 45 sites were replaced with uPVC riser pipes. After the pipe replacement of GI riser pipes, the community used the handpumps that had previously been abandoned, with unsafe water sources being used instead. The pipe replacement study was successful, with the water users returning to previously abandoned boreholes which had clear, rust-free water. 
  • There is some evidence of other projects and organisations starting to use either stainless steel riser pipes, or uPVC riser pipes with stainless steel connectors in their projects, but documentation is limited. While stainless steel riser pipes have been used effectively, there are also some outstanding technical issues – particularly in relation to the removal of narrower diameter riser pipes, which require suitable tools that are not in the standard India Mark II toolkit. Further, the use of uPVC pipes has also been found to be problematic, as they need to be cut on removal and cannot easily be re-threaded. However, at least one NGO in Zambia has been using an alternative, comprising uPVC with stainless steel couplers which is available on the Zambian market. A further complication is that some parts of Zambia appear to exhibit naturally occurring iron. Tests are available to determine whether iron is naturally occurring or a result of corrosion, but there is no comprehensive map to indicate areas at risk of high levels of geogenic iron.

While stainless steel riser pipes have been used effectively, there are also some outstanding technical issues – particularly in relation to the removal of narrower diameter riser pipes, which require suitable tools that are not in the standard India Mark II toolkit. Further, the use of uPVC pipes has also been found to be problematic, as they need to be cut on removal and cannot easily be re-threaded. However, at least one NGO in Zambia has been using an alternative, comprising uPVC with stainless steel couplers which is available on the Zambian market. A further complication is that some parts of Zambia appear to exhibit naturally occurring iron. Tests are available to determine whether iron is naturally occurring or a result of corrosion, but there is no comprehensive map to indicate areas at risk of high levels of geogenic iron.  Despite all of the efforts to date, and notwithstanding the widespread nature of rapid handpump corrosion of GI riser pipes and pump rods, the problem still persists in 2023. 

Potential Next Steps for GRZ / International Donor Community / Universities 

  1. Revise the National Water Policy to include aggressive groundwater in community boreholes 
  2. Restrict Types of Handpumps to Certain Regions. 
  3. Enact a Law and a Statutory Instrument on Aggressive Groundwater in Community Boreholes. 
  4. Incentivise the private sector for provision of corrosion-resistant pipes and rods 
  5. Regulation of Quality of Handpumps by Zambia Bureau of Standards. 
  6. Standardise Handpumps Used in Zambia. 
  7. Further studies and replacement of galvanised iron riser pipes. 
  8. Further Research Studies on the phenomenon of naturally occurring iron in ground and surface water and 
  9. Research Studies on Saline Water in Western Province

You are invited to access the presentations HERE, along with the session’s concept and the study report:  Nkhosi. J and Danert, K. (2023). ‘Stop the Rot: History of the Rapid Handpump Corrosion Problem in Zambia and Potential Next Steps. Action research on handpump component quality and corrosion in sub-Saharan Africa’. Ask for Water GmbH, Skat Foundation and RWSN, St Gallen, Switzerland. https://doi.org/10.13140/RG.2.2.27489.28006.

If you would like to dive deeper into the enriching exploration of water challenges and solutions through the Stop the Rot initiative, visit this page.

About the author:

 Javan Nkhosi presenting at ZAWAFE 2023

Javan Nkhosi is a Zambian water professional. He has worked in the rural water sub-sector for more than 25 years on many water supply projects funded by the government, NGOs and donor agencies as a private consultant across Zambia. He has a passion for improving water supply to the unreached areas of rural Zambia. He holds a Diploma in Agricultural Engineering from NRDC, Lusaka, Advanced Diploma in Water Engineering from the Copperbelt University and an MSc in Project Management from the University of Lusaka. He is a Registered Engineer with Engineering Institute of Zambia (EIZ) and also a member of the Association of Consulting Engineers of Zambia (ACEZ) , an affiliate of the International Federation of Consulting Engineers (FIDIC). 

References:

Understanding why waterpoints fail

By Vincent Casey, Technical Support Manager, and Richard Carter.  (originally posted on the WaterAid website)