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Introduction Back Next
Graphic of a map with an impact adjustment variable pamphlet and examples pamphlet.

The first step in the scoring process is to determine whether an element deserves credit and, if so, how many points. This step is described in the sections on the 300, 400, 500 and 600 series of activities. For example, having parks in the floodplain receives 725 points under preserving open space in Activity 420 (Open Space Preservation).

The next step is to adjust the credit points for an element to reflect its impact on flood losses. For example, a community that has preserved large areas as open space should receive more credit than one that is allowing most of its floodplain to be developed.

A community receives the full 725 points only if it has preserved all of its floodprone areas as open space. If only part of the floodplain is kept open, then the score of 725 point should be adjusted to reflect how much is preserved. For example, if half of the floodplain is in parks, then the community should get half of the 725 points. That is the basis for the impact adjustment step.

The impact adjustment is included in the credit calculation formula by multiplying the element score by the impact adjustment ratio. The ratio multiplier ranges from 0.05 to 1.0, i.e., from 5 percent to 100 percent of the maximum possible. In the example just discussed where half the floodplain is preserved as open space, the score would be 725 x 0.5 = 362.5.

Click on a link to the left to learn more about calculating different impact adjustments or click on a link below to learn more about impact adjustment variables and examples.

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