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H_onbest is the depth of the channel below the revetment.
M_bestorting is the horizontal projection of the length of the revetment.

In case no slope protection is present, if over the entire channel depth softening sensitive sand is present, this margin is thus equal twice the fictive channel depth (M = 2 H).
The inclined part of the observation profile in line with the horizontal portion. The inclination of the slope depends on the channel depth:

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• The total slope (channel edge-channel bottom) is on average steeper than or equal to 1 : [7 × (H_R/24)^(1/3) ], in which H_R is defined in the figure defined  below.
• Breaching is possible (see paragraph below called "Breaching criteria")

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If the criteria of occurrence is not met, the Global and the Overall checks SUCCEED. 

H_R [m] is the height of the submerged slope in its most unfavourable situation during the assessment period and determined with:

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in which:

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Image Added (with h_dijk is dike height)

Image Added(with d is waterdepth and Dh_onder part of the channel slope that lies above the water level during extreme low tide).

B is width of the foreland. In case of a "schaardijk" B = 0.

• cota_R is equal to cota_onder.
• H [m] is the height of the submerged slope  (Image Added)

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Breach flow criteria:

This criterion is adopted from step 5 of CUR Aanbeveling 113, 2008.

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