Nationwide permit program: Unknown adverse impacts on the commonwealth of the Northern Mariana Islands' wetlands

Of the 39 Nationwide Permits (NWPs) that came into effect on 11 February 19 97 11 authorize activities that could impact Commonwealth of the Northern M ariana Islands (CNMI) wetlands. Because managers of CNMI wetlands lack an a ccurate scientific basis for determining the significance of proposed wetla nd impacts, the CNMI denied and conditioned Clean Water Act Section 401 Wat er Quality Certifications and Coastal Zone Management Act Section 307 consi stency concurrences for these 11 NWPs to reduce the likelihood of the U.S. Army Corps of Engineers (Corps) authorizing more than minimal adverse wetla nd impacts under the NWP program. The CNMI decided that the benefits of req uiring a more stringent review process outweigh the costs of increasing the regulatory burden on developers. A review of authorized CNMI wetland impac ts indicates that the loss of wetland quantity under the NWP program on Sai pan is minimal. However managers do not know if the site specific and cumul ative loss of wetland quality-wetland functional performance and provision of valued services-is significant. The Corps authorized 7 projects under NW Ps that impacted CNMI wetlands. These 7 projects impacted 10 of Saipan's 37 freshwater wetlands and filled approximately 3.6 hectares or 1.5% of the i sland's total freshwater wetland area. Seven of these 10 affected sires wer e isolated wetlands. Nationwide, the Corps does not know if the cumulative loss of wetland area, functions, and values authorized under the NWP progra m has been minimal because the Corps has incomplete data on wetland impacts . Also, because most regions of the United States lack standardized assessm ent methods that estimate changes in functional performance and provision o f valued services by local wetland classes, because many regions do not hav e the ability to define thresholds for cumulative wetland impacts, and beca use even small, isolated and temporary wetlands may possess valued function s, the Corps does not know if wetland impacts authorized under the NWP prog ram have been minimal. The Corps lacks an accurate basis for defining what constitutes a more than minimal adverse wetland impact to implement the NWP Program. Regulators assume that conserving wetland area prevents a net los s of functional performance and the provision of valued wetland services, b ut they have no means to confirm the accuracy of this assumption. Condition ing and denying the use of NWPs that could be used to authorize wetland imp acts creates a more stringent review process bur still results in the conti nued authorization of unknown wetland impacts under provisional NWPs and In dividual Permits. A proposed solution is to develop regional wetland assess ment methods for each wetland class to allow for the management of the proj ect-specific and cumulative effects of wetland degradation on wetlands func tional performance and provision of valued services. This provides wetland managers with the requisite information to condition relevant NWPs to ensur e that no more than minimal adverse wetland impacts are authorized in their region.