Borehole Water Quality in Eastern Kenya: What to Test, What Problems to Expect & What to Do Next

1) Why quality matters (homes, farms, institutions)

Water quality affects different users in different ways. Homes care about taste, safety and plumbing damage. Farms care about crops, soil and irrigation clogging. Institutions care about hygiene, safety and continuity for many users.

2) When to test after drilling

Test after drilling and development, once water runs clear and the borehole stabilizes. If you test too early, results can be misleading because drilling disturbance can temporarily change turbidity and some readings. For drinking/cooking or institutions, don’t connect final supply without quality confirmation.

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  After development
  Let the borehole run clean before sampling.
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  Before final plumbing
  Results can affect filter choice, pipe material, and system layout.

3) Core tests to request (must-have list)

Start with a practical core panel that answers the big questions fast. You can always add more tests later if the core panel shows a concern.

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  EC / TDS
  Quick indicator of salinity (dissolved salts).
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  pH
  Affects corrosion and treatment decisions.
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  Total hardness
  Scaling risk for heaters, pipes and sprinklers.
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  Iron / Manganese
  Staining, taste, clogging and filter load.
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  Fluoride
  Important in some regions; check before drinking use.
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  Nitrates
  Possible contamination indicator (agriculture/septic).
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  Bacteriological test
  Basic safety indicator (especially for drinking/institutions).

4) Salinity (EC/TDS): what it means

Salinity is the “salts dissolved in water” story. High salinity can make water taste salty, corrode fittings, and reduce crop yields over time depending on crop tolerance and soil conditions. EC (electrical conductivity) and TDS (total dissolved solids) are common screening metrics.

5) Hardness: scaling, heaters & pipes

Hard water causes scaling—white deposits in kettles, heaters, pipes and sprinklers. On farms, hardness can clog nozzles and reduce irrigation uniformity. In buildings, hardness increases maintenance costs and reduces equipment life.

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  Signs
  White crust, reduced flow, noisy heaters, frequent shower-head clogging.
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  What helps
  Softening or targeted treatment; also plan easier cleaning points in the system.

6) Iron & manganese: staining and clogging

Iron and manganese can stain tanks and fixtures and may create a metallic taste. They also load filters quickly and can clog irrigation lines when oxidation causes particles to form. If you see reddish/brown staining, iron is a likely suspect.

7) Fluoride: why it matters

Fluoride is important to check if you plan drinking use. Some regions can have elevated fluoride levels naturally due to geology. If fluoride is high, you plan appropriate drinking-water treatment or alternative supply for drinking/cooking.

8) Nitrates & bacteria: contamination risks

Nitrates can increase due to surface contamination sources like septic systems, animal areas, or fertilizer use. Bacteria risk increases with poor headworks sealing, bad drainage around the borehole, or dirty storage tanks. These are often system/hygiene problems, not “the aquifer is bad.”

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  Protect the borehole head
  Drainage away from the borehole reduces contamination risk.
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  Tank cleaning schedule
  Dirty tanks can undo all your treatment efforts.

9) Treatment options (what works for what)

Treatment should match the problem. Don’t buy “one filter to solve everything.” A good provider will map treatment to test results and intended use (drinking vs irrigation).

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  Particles/turbidity
  Sediment filtration, proper development, and good screens/gravel pack.
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  Iron/manganese
  Oxidation/aeration + filtration; ensure maintenance access.
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  Hardness
  Softening solutions where needed; protect heaters and sprinklers.
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  Salinity (high TDS/EC)
  Specialized treatment (e.g., RO) or blending/usage adjustment where possible.
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  Bacteria
  Disinfection strategy + sealing + tank hygiene.
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  Fluoride
  Targeted drinking-water treatment; plan drinking points separately if needed.

10) System design to protect quality (tanks, pipes, hygiene)

Even great water can become unsafe or unpleasant if the system is poorly designed. Storage tanks need cleaning access, covers, and a schedule. Pipes should avoid dead-ends where water stagnates, and headworks should drain away from the borehole.

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  Covered tanks
  Prevents contamination and algae issues.
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  Accessible filters
  If filters are hard to service, they won’t be serviced.
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  Drainage + sealing
  Protect the borehole head from runoff and animal areas.

11) Common mistakes (and cheap fixes)

Quality problems often persist because the wrong solution was applied. Fixing the system basics can solve a surprising number of “water quality” complaints.

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  Buying random filters without test results
  You spend money and still don’t solve the real issue.
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  Dirty tanks
  Tank hygiene is a top cause of taste/odor/bacteria complaints.
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  Poor headworks drainage
  Surface runoff and animal activity can contaminate the area.
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  No maintenance access
  Filters and treatment fail if they’re impossible to service regularly.

12) Mini decision tool (quick guidance)