6 were not compliant, 2 were never attempted, and 13 permits were never completed. The remaining projects were only partially successful in meeting the permit requirements. Eight studies of five state permitting programs examined whether attempts at mitigation met permit conditions (see Table 6–13). Compliance with the permit was measured by the area of created or restored wetlands. The results indicate that the compensatory wetland mitigation area was often less than the permitted area.

Mitigation sites have also been evaluated using more subjective measures. DeWeese (1994) evaluated 30 projects in California to determine mitigation compliance using a 10-point scale based on professional judgment. About half of the sites were at least 5 years old. DeWeese ranked only 1 of the 30 sites high, 13 were average or above average, and 6 were below average (Table 6–14). Two sites had low value, and two others were judged to have no value. The average value was 4.7 for 30 mitigation projects. There was no net loss in area as a result of permitting, but there was a net loss in ecological functionality.

Allen and Feddema (1996) examined 75 sites in California using three simple criteria evaluated subjectively: weed invasion, plant cover, and vegetation status. They found a 69% “success rate” and estimated that 77 ha replaced 81 ha lost, for a net loss of 5%. Storm and Stellini (1994) found a mixed result in their review of 17 compensatory mitigation projects in Washington (Table 6–15). Fifty-three percent could not be verified as being in compliance with the permit, 29% were verified as being out of compliance, and two-thirds were not ecologically equivalent to the wetlands lost through the permitting program. Monitoring was done for only

TABLE 6–13 Compliance (Area Basis) for Mitigation That Was Attempted Based on Field Inspection or Monitoring Reports

Location

No. of Permits

Impacted Hectares

% Area Gain (loss)

Source

California

Orange County

68

128

(92)

Sudol (1996)

San Diego County

N.A.

102

(8)

Fenner (1991)

Southern Sacramento

75

80

(8)

Allen and Feddema (1996)

San Francisco

30

168

44

DeWeese (1994)

Florida

29

269

(32)

Lowe et al. (1989)

Indiana

31

14

10

J.T.Robb (personal commun. 2000)

Ohio

5

24

(33)

Wilson and Mitsch (1996)

Tennessee

50

38

(13)

Morgan and Roberts (1999)



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