A flood line study gives you one number.

The height a 1-in-100-year flood will reach on your plot, in centimetres, with the floor we'd set above it and the drawings that prove it. This one is a sample plot on a wadi bank in Muscat.

+1.20m

Flood line sheetSample plot · Muscat · 1-in-100-year stormPlotfloor +1.50 mWadi, flows east →Section A–A+1.20+1.50 floorFlood line+1.20 mFloor we would set+1.50 mFreeboard0.30 mCHARTEREDENGINEER Miqyas
You send
The plot's location and its survey, and a sketch of what you want to build if you have one.
We model
The catchment above it, the 1-in-100-year storm, and the path the water takes past your plot.
You get
The line sheet: your level, the floor we'd set, and what to build, signed by a chartered engineer.
Find your plot's lineAbout three weeks, at a fixed fee agreed before we start.

How a study runs.

  1. Day 1

    You send the plot.

    Its location, the survey if there is one, and what you want to build.

  2. Week 1

    We walk it.

    An engineer visits the plot and the wadi above it, and marks what a survey misses: walls, culverts, the silt lines old floods left.

  3. Weeks 1–2

    We model the storm.

    The catchment, the 1-in-100-year rainfall, and the path the water takes past your plot.

  4. Week 3

    We set the line.

    The flood level on your plot, checked against the marks the last floods left.

  5. Week 3

    You get the sheet.

    Signed, with the floor level and what to build, set out for the authority that approves it.

What the sheet says.

Flood line sheetSample plot · Muscat · 1-in-100-year stormPlotfloor +1.50 mWadi, flows east →Section A–A+1.20+1.50 floorFlood line+1.20 mFloor we would set+1.50 mFreeboard0.30 mCHARTEREDENGINEER Miqyas
The flood line: +1.20 m
The height a 1-in-100-year flood reaches on this plot, measured from the plot's datum. One number, not a range.
The floor: +1.50 m
Where we'd set the ground floor: the line plus a freeboard of 30 cm, for waves, debris and the storm that's worse than the model.
The section
The wadi, the bank and your plot cut through at the place it matters, with the line drawn across it. The drawing an architect builds from.
The signature
A chartered engineer signs every sheet. If the line is wrong, it's ours.

A fixed fee. About three weeks.

We agree the fee before we start, from the plot's size and the wadi above it. From the site visit to the signed sheet takes about three weeks.

If the plot sits in a wadi system we haven't modelled yet, we'll say so first, and tell you why it takes longer.

What owners and architects ask

Why the 1-in-100-year flood?

It's the flood with a one-in-a-hundred chance of happening in any year, the standard most authorities in the region plan to. For a hospital, a school or a power station, we model a rarer storm too.

My plot isn't in a wadi. Do I need this?

If water from higher ground can reach it, yes. Many plots we study look dry and flat; the wadi is two hundred metres uphill.

Will the approving authority accept it?

The sheet is signed by a chartered engineer and set out the way approving authorities expect: the level, the method, the drawings.

Can you tell me the line over the phone?

No. A number without the walk and the model is a guess, and a guess is what we're here to replace.

Find your plot's line before the rain finds it.

Find your plot's line Or write to [email protected]