How do you check a soakaway test in Hargeisa?

A soakaway test in Hargeisa starts with digging a trial hole at the soakaway position, filling it with water, and timing how fast the level drops. Check it by asking for that log in writing: hole location, depth, groundwater level, water depth, and each refill and reading. Without it you only have a claim, not a test.

What should the trial hole log show?

The log should let someone who was not on site repeat the test. Ask for the plot reference, the hole's grid position, the excavated depth, and the depth at which groundwater or seepage appeared. It should record the water level at the start and at fixed intervals after each refill, with the times written down. If the pit sat overnight, the soaking period and the weather since excavation belong in the record. A photograph of the hole next to a tape is useful, but it does not replace the numbers. Ask the engineer whether the hole depth matches the invert level the drainage design assumes. Comparison with a second hole, or with a nearby borehole log, tells you whether the result describes the plot or one patch of ground. The Hargeisa municipal engineer's office may hold borehole logs for the area, so it is worth asking whether it does.

How is the soakage rate calculated?

Ask to see the calculation, not just a pass or fail. The drop in water level over the timed interval, the wetted area of the pit, and the resulting infiltration rate should all appear on one page. A rate taken from a single reading during a fast first fill is not the same as one taken after the pit has soaked. Ask which value was used for design and where that value came from. General practice is to test more than once, at the design depth, with the pit refilled to the same level each time, but confirm the number of tests and the required rate against the project's specification or the engineer. If the measured rate is lower than the design assumed, the design changes, not the test result. If the rate is higher than expected, ask how the pit will be protected from silt so it still drains in a few years.

Who signs off before backfilling?

Backfilling ends the test. Before the pit is closed, the supervisor, the contractor's engineer and the client's representative should agree in writing on the hole location, the readings, the calculated rate and the acceptance decision. Ask the contractor what the contract requires for hold points and records, and check what it allows if the record is missing. Ask for the test pit to be marked on the site drawing so the soakaway is built in the ground that was tested. If the pit is built somewhere else, the test describes a different hole. Where the plot is steep or has been filled, ask whether more than one hole was tested. The signed sheet is also the document any later drainage repair will be judged against.

What to do next

Write to the contractor today and ask for the soakaway trial hole log, the infiltration rate calculation and the signed acceptance sheet. Set a date to walk the plot and mark the tested hole on the drainage drawing before the pit is backfilled. If any document is missing, ask for a repeat test at the design depth.