(4 credits available; 1 required)
To encourage the identification of flood risk and implement mitigation measures where required.
If a flood risk assessment (FRA) has been carried out, what was its scope and which flood risk level was assigned to the asset?
|Credits||Answer||Select a single answer from B,C,E,& F; if B or C has been selected, answer D is also available. Answer G is in addition to all others.|
|0||A||Question not answered|
|1||B||FRA scope included Fluvial (rivers) and Tidal (sea) sources and flood risk from these sources is Medium or High|
|2||C||FRA scope included all sources and flood risk is Medium or High|
|+2||D||Flood mitigation measures were required and have been implemented|
|3||E||FRA scope included Fluvial (rivers) and Tidal (sea) sources flood risk from these sources is zero or low|
|4||F||FRA scope included all sources and flood risk is zero or low|
|Exemplary||G||The Flood Risk Assessment contains an allowance for climate change|
|Criterion||Assessment criteria||Applicable answer|
Flooding from the following sources must be taken into account:
|2||Flood risk maps produced by a Local or National Authority can form the basis of a Flood Risk Assessment but will not be sufficient on its own to demonstrate compliance. Assessors should verify which sources of flooding flood risk maps cover when awarding credits.||B,C,E - G|
Flood Risk Assessments need to be undertaken by a relevant organisation/authority or a competent individual:
|B,C,E - G|
|4||It must be demonstrated that recommendations have been implemented.||D|
Exemplary level credit:
Answer option G can be select independently of which other answer option has been selected.
An allowance for climate change should be based on a Medium or High Emissions Scenario from a robust Climate Model. This should cover a reasonable time period for the building, such as the 2050s or beyond.
Checklists and Tables
No National definitions of Flood Risk
In countries that do not have a definition of flood risk the following definitions can be used.
Table 25: Flood risk zones
|Fluvial (rivers)||Tidal (sea)|
|Low annual probability of flooding||Less than 1 in 1000 chance of flooding (< 0.1%)||Less than 1 in 1000 chance of flooding (< 0.1%)|
|Medium annual probability of flooding||Between 1 in 100 and 1 in 1000 chance of flooding (1%– 0.1%)||Between 1 in 200 and 1 in 1000 chance of sea flooding (0.5%–0.1%)|
|High annual probability of flooding||1 in 100 or greater chance of river flooding (>1%)||1 in 200 or greater chance of flooding from the sea (>0.5%)|
|-||The evidence below is not exhaustive, please also refer to the ‘BREEAM evidential requirements’ section in the scope of the Guidance for appropriate evidence types which can be used to demonstrate compliance.|
Flood risk maps showing the following:
|3||FRA from relevant body or competent individual, including evidence of their competence|
|4||Photographic or documentary evidence that the mitigation measures have been implemented|
|5||Highlighted sections of the FRA showing the Emissions Scenario, Climate Model used and timeframe for the allowance for climate change|
An individual (or individuals) with qualifications and experience relevant to assessing flood risk, designing flood prevention measures and calculations. Where complex flooding calculations and prevention measures are required, this must be a specialist hydrological engineer.
Functional flood plain:
A zone that comprises land where water has to flow or be stored in times of flood.
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