Workshop Table of Contents

Saltcedar Management Workshop, June 12, 1996


Invasive Weed Control and the Need for Section 404 Clean Water Act Permits: the Dual Role of the Army Corps of Engineers

Eric D. Stein
U.S. Army Corps of Engineers
Los Angeles District, Regulatory Branch
P.O. Box 2711 Los Angeles, CA 90053

Introduction

Over the last 25 years the riparian areas of the southwest have become infested with two non-native weed species known as giant reed (Arundo donax) and saltcedar (Tamarix spp.). Control of these invasive weeds often requires an integrated strategy, which can include prescribed fire, herbicide application, and mechanized clearing. When mechanized clearing is employed in an aquatic area, a permit may be required from the United States Army Corps of Engineers (Corps) pursuant to Section 404 of the Clean Water Act. In addition to its role as a regulatory agency, the Corps can be a valuable partner in the battle against riparian invaders, such as giant reed and saltcedar. Both these roles are discussed in this paper.

The Clean Water Act

The primary regulatory mechanism for the protection and management of the nation's waters and wetlands is Section 404 of the Clean Water Act (CWA). Section 404 is administered by the Corps according to regulations published in the Federal Register on July 25,1975. The main objective of the CWA is "to restore and maintain the chemical, physical, and biological integrity of the nation's waters." Section 404 of the CWA regulates the discharge of dredged material, placement of fill material, or excavation within waters of the United States and authorizes the Secretary of the Army, through the Chief of Engineers, to issue permits for such actions. Permits can be issued for individual projects (individual permits) or for general categories of projects (general permits). Waters of the U.S. are defined by the CWA as "rivers, creeks, streams, and lakes extending to their headwaters and any associated wetlands". Wetlands are defined by the CWA as "areas that are inundated or saturated by surface or groundwater at a frequency and duration sufficient to support a prevalence of vegetation typically adapted for life in saturated soil conditions".

In an attempt to reduce administrative paperwork, Section 404 contains provisions for the issuance of general permits which cover classes of activities considered to have minimal adverse environmental incremental or cumulative impacts on waters of the U.S. and, therefore, not requiring individualized permit review. General permits can be issued on a local, regional, or nationwide level. There are currently 40 general permits which have been issued on a nationwide level (hereafter referred to as the "nationwide permits"). Nationwide permits cover activities such as road crossings, utility line crossings, maintenance, navigational aids, and bank stabilization. There is a great deal of controversy regarding whether or not the cumulative impacts of the nationwide permits are minimal. This is particularly true in the case of Nationwide Permit 26, which allows for discharges of fill into up to 10 acres of isolated waters above headwaters. In the Los Angles Corps District, which covers Southern California and Arizona, approximately 75 % of all Corps actions are nationwide permits.

Procedures for Permit Processing (in the Los Angeles District)

The application process often begins during the conceptual design phase of a project with a preapplication meeting. In this meeting potential concerns of the Corps and other resource agencies are discussed and the applicant is encouraged to redesign their project, if necessary, to avoid or reduce impacts to aquatic resources. Applicants are also encouraged to explore the possibility of reducing the impacts of their project to a level where a nationwide permit may be used.

Once a formal application is received, it is assigned to a project manager who will review the case and ultimately make a recommendation to the District Engineer regarding issuance of a permit. Because permit evaluation is limited to the impacts to areas under jurisdiction of the Corps, the project manager must make an initial jurisdictional determination. For non-tidal waters, Corps jurisdiction extends to the ordinary high-water mark (OHWM), which is defined as:

the line on the shore established by the fluctuations of water and indicated by physical characteristics such as a clear, natural line impressed on the bank; shelving; changes in the character of soil; destruction of terrestrial vegetation; the presence of litter or debris; or other appropriate means that consider the characteristics of the surrounding areas (33 CFR Section 329.11)

The shoreward limit of Corps jurisdiction for navigable waters is the mean higher high water mark (MHHM), defined as:

extends through the entire surface and bed of all water bodies subject to tidal action to the line on the shore reached by the plane of the mean (higher) high water, which is defined as the average of the higher of the two daily high tides (33 CFR Section 329. 12)

In order to meet the jurisdictional definition of wetlands an area must contain fulfill three wetland criteria (USACOE, 1987):

1. at least 50% of the vegetation on the site must be hydrophytic
2. the soils must be classified as hydric or have hydric indicators, such as mottles, oxidized rhizospheres, or gleying
3. the area must be saturated or inundated for greater than five percent of the growing season. In Southern California this is equal to eighteen days.

Discharges of dredged or fill material resulting from normal farming, ranching, and silviculture culture activities are exempt from Section 404 permit requirements under Section 404(f) of the CWA.

Once the limits of Corps jurisdiction are resolved, the project manager determines whether or not the activity meets the terms and conditions of one of the nationwide permits. If a project qualifies under one of the nationwide permits, a letter may be issued verifying compliance with the nationwide permit program. Verification of compliance may be conditioned with specific terms regarding construction protocol, use of best management practices, avoidance of endangered species habitat, and mitigation requirements to ensure that the project will have minimal incremental or cumulative impacts to aquatic resources. If a project meets the general terms and conditions of a nationwide permit, but will result in greater than minimal impacts, the District Engineer (DE) may take discretionary authority and require the project to be processed as an individual permit. The review process for a nationwide permit is generally less extensive than for an individual permit and can often be completed within thirty days.

Projects which cannot be permitted under a nationwide permit must undergo a more extensive review under the individual permit process, which typically takes 120 days. The Corps decides whether to issue an individual permit based on an evaluation of the probable impacts, including cumulative impacts, of the proposed activity. According to Corps regulations, permits should not be issued for activities which will create ''significant'' degradation of the waters of the U.S or have "significantly adverse effects on wetlands values". However, the CWA provides no clear definition of "significant" (Hirsch, 1988).

The evaluation process for an individual permit is based on guidelines established under Section 404(b)(1) CWA and on the "public interest review" procedures. The public interest review involves a broad qualitative evaluation of a project's benefits and detriments. Corps regulations identify twenty-one factors which are relevant to permit review. These factors are conservation, economics, aesthetics, general environmental concerns, wetlands, historic properties, fish and wildlife values, flood hazards, floodplain values, land use, navigation, shore erosion and accretion, recreation, water supply and conservation, water quality, energy needs, safety, food and fiber production, mineral needs, consideration of property ownership, and the general needs and welfare of the people. The public interest review is facilitated by the issuance of a 15-30 day Public Notice soliciting comments from the public and resource agencies, such as U . S . Fish and Wildlife Service, U . S . Environmental Protection Agency, and California Department of Fish and Game regarding the proposed project. A public hearing may be held for highly controversial projects.

The Section 404(b)(1) guidelines are often considered the driving force in the Corps permit process (Liebesman and Hundemann, 1992). The 404(b)(1) guidelines prohibit discharges of dredged or fill material if there is a less environmentally damaging practicable alternative. Practicability is determined based on technological, economic, social, and logistic considerations. If a proposed project has greater than significant impacts, attempts must be made to avoid and minimize impacts. Impacts which cannot be avoided must be mitigated to a level where the net impacts to waters of the U.S are not significant. In some cases, projects which result in significant impacts may be permitted if they provide a substantial benefit to the public, such as projects affecting national security or considerable production of energy.

The Corps must ensure that permitted projects comply with all other applicable federal resource protection laws such as the Endangered Species Act, the National Historic Preservation Act, and the Coastal Zone Management Act (see Section 2.3.4). In addition, certification that the proposed activity will comply with all applicable effluent limitations and water quality standards of Section 401 of the CWA is needed prior to issuance of a Section 404 permit. The need for a Section 404 permit constitutes a federal action under the National Environmental Policy Act (NEPA). Therefore, during the review of a proposed project an Environmental Assessment (EA) is prepared according to NEPA guidelines. If the impacts of the proposed activity are determined to be significant according to NEPA, an Environmental Impact Statement (EIS) must be prepared and reviewed according to all NEPA requirements.

If a proposed project complies with all the NEPA requirements, the 404(b)(1) guidelines, is determined not to be contrary to the public interest, and does not violate any federal resource protection laws, the Corps will issue an individual permit authorizing the proposed discharge of dredged or fill material into water of the U.S or wetlands. If a proposed project violates any of the above, then the Corps must deny the Section 404 permit. Of the estimated 100,000 activities regulated annually by the Corps, 83 % are authorized by general permits, such as the nationwide permits. Less than 5% of individual permit applications are denied annually; however, up to 30% of individual permit applications are withdrawn. (Liebesman and Hundemann, 1992; Thompson and Yocom, 1993). Under Section 404(c) EPA has the authority to override a Corps' decision to grant a permit if they feel the discharge would result in "unacceptable adverse effects on municipal water supplies, shellfish, fishing areas, wildlife, or recreation areas. Since 1972, only 11 vetoes have been initiated (Thompson and Yocom, 1993).

The Corps of Engineers as a Partner in Invasive Weed Control

Effective management of invasive weeds requires watershed-scale efforts, with weed control beginning in headwaters areas and proceeding downstream to minimize reinfestation of previously treated areas. Such large-scale efforts are often beyond the resources of individual organizations. The widespread jurisdiction of the Corps of Engineers allows Corps representatives to gather information on needs and projects throughout watersheds, putting the Corps in a position to coordinate efforts among various organizations. Two such coordinated efforts are currently ongoing in the Santa Ana and Santa Margarita watersheds in southern California. These watersheds are two of the largest in southern California (2,450 square miles and 750 square miles, respectively) and both encompass multiple counties, cities, special districts, and military installations. The Corps is working with federal, state, and local agencies, the military, and private groups, such as The Nature Conservancy, to help coordinate invasive weed control programs in these watersheds. Exposure to multiple control programs and strategies has allowed the Corps to develop technical expertise and help disseminate knowledge gained through successes and failures.

Corps' regulations, guidelines, and Memorandum of Agreement (MOA) allow for compensatory mitigation to be performed in order to offset the unavoidable impacts associated with permitted activities. Invasive weed removal can serve as compensatory mitigation for certain projects affecting aquatic resources and can be incorporated into the Best Management Practices of many projects. The Corps can require permittees whose activities involve temporary or construction related disturbance of aquatic areas to ensure that the disturbed areas are not invaded by saltcedar, giant reed, or other weeds. This can help reduce proliferation of infestation, as often of Section 401 of the CWA is needed prior to issuance of a Section 404 permit. The need for a Section 404 permit constitutes a federal action under the National Environmental Policy Act (NEPA). Therefore, during the review of a proposed project an Environmental Assessment (EA) is prepared according to NEPA guidelines. If the impacts of the proposed activity are determined to be significant according to NEPA, an Environmental Impact Statement (EIS) must be prepared and reviewed according to all NEPA requirements.

If a proposed project complies with all the NEPA requirements, the 404(b)(1) guidelines, is determined not to be contrary to the public interest, and does not violate any federal resource protection laws, the Corps will issue an individual permit authorizing the proposed discharge of dredged or fill material into water of the U.S or wetlands. If a proposed project violates any of the above, then the Corps must deny the Section 404 permit. Of the estimated 100,000 activities regulated annually by the Corps, 83% are authorized by general permits, such as the nationwide permits. Less than 5% of individual permit applications are denied annually; however, up to 30% of individual permit applications are withdrawn. (Liebesman and Hundemann, 1992; Thompson and Yocom, 1993). Under Section 404(c) EPA has the authority to override a Corps' decision to grant a permit if they feel the discharge would result in "unacceptable adverse effects on municipal water supplies, shellfish, fishing areas, wildlife, or recreation areas. Since 1972, only 11 vetoes have been initiated (Thompson and Yocom, 1993).

The Corps of Engineers as a Partner in Invasive Weed Control Effective management of invasive weeds requires watershed-scale efforts, with weed control beginning in headwaters areas and proceeding downstream to minimize reinfestation of previously treated areas. Such large-scale efforts are often beyond the resources of individual organizations. The widespread jurisdiction of the Corps of Engineers allows Corps representatives to gather information on needs and projects throughout watersheds, putting the Corps in a position to coordinate efforts among various organizations. Two such coordinated efforts are currently ongoing in the Santa Ana and Santa Margarita watersheds in southern California. These watersheds are two of the largest in southern California (2,450 square miles and 750 square miles, respectively) and both encompass multiple counties, cities, special districts, and military installations. The Corps is working with federal, state, and local agencies, the military, and private groups, such as The Nature Conservancy, to help coordinate invasive weed control programs in these watersheds. Exposure to multiple control programs and strategies has allowed the Corps to develop technical expertise and help disseminate knowledge gained through successes and failures.

Corps' regulations, guidelines, and Memorandum of Agreement (MOA) allow for compensatory mitigation to be performed in order to offset the unavoidable impacts associated with permitted activities. Invasive weed removal can serve as compensatory mitigation for certain projects affecting aquatic resources and can be incorporated into the Best Management Practices of many projects. The Corps can require permittees whose activities involve temporary or construction related disturbance of aquatic areas to ensure that the disturbed areas are not invaded by saltcedar, giant reed, or other weeds. This can help reduce proliferation of infestation, as often happens in recently disturbed areas. When on-site mitigation is not appropriate, the Corps can direct permittees to mitigate the impacts of their activities by removing invasive weeds in strategic areas of the watershed; thereby contributed to the overall control program.

The recent rise in popularity of mitigation banks provides another tool for use in large-scale invasive weed control programs. Wetland mitigation banks strive to establish large, contiguous wetland areas which can be used to mitigate for a number of independent impacts. This allows eligible permittees to purchase compensatory mitigation credits from another entity that has already produced and banked them, thereby eliminating the need to produce compensatory mitigation areas on-site (IWR, 1994). The Corps has been an active participant in the establishment a mitigation bank in the Santa Ana River which is focused on invasive weed removal. The goal of the Santa Ana River Mitigation Bank (SARMB) is to reestablish native riparian ecological diversity and other riparian functions through the removal of invasive weeds. The 137 acre SARMB is located in a portion of the Santa Ana River where the native riparian habitat has been replaced with monotypic stands of Arundo donax (giant reed). The establishment of this mitigation bank should provide the resources to remove giant reed from a ecologically important reach of the Santa Ana River. At the same time, the proposed SARMB will provide an ecologically meaningful and economically efficient alternative for permittees fulfill compensatory mitigation requirements of Corps permits. If successful, this mitigation bank could serve as template for the establishment of other mitigation banks focused on invasive weed removal.

It should be clarified that a Section 404 permit is not always necessary to undertake an invasive weed removal program. Prescribed burns, herbicide application, and using hand-held tools to cut plants do not require authorization from the Corps of Engineers. Corps permits are necessary when mechanized land clearing, excavation, stockpiling, or other activities occur which affect the substrate of an aquatic area (e.g. rivers, lakes, wetlands). Many smaller (i.e. less than ten acres) invasive weed removal projects may qualify for authorization by nationwide permits. However, in recognition of the fact that invasive weed removal generally results in environmental enhancement, the Los Angeles District of the Corps of Engineers has proposed issuance of a General Permit, which would authorize mechanized removal of invasive weeds from waters of the U.S. in southern California. If this General Permit is issued, it would provide for expedited approval of mechanized invasive weed removal contingent upon following a series of predetermined environmental protective measures. This General Permit would also allow people to take advantage of opportunities for invasive weed control which arise immediately following flood or fire.

Corps participation on interagency teams allows for protection of resources and the public interest, coordination of large-scale invasive weed control efforts, dissemination of technical information, and identification of opportunities to ease regulatory hurdles to invasive weed control. This allows the Corps to fulfill the dual role of regulatory agency and partner in invasive weed eradication.

References

Hirsch, A., Regulatory Context for Cumulative Impact Research. Environmental Management, Vol. 12(5), pp. 715-723, 1988

Institute for Water Resources (IWR), Wetland Mitigation Banking, IWR Report 94-WMB-6, Washington, D.C., 1994

Liebesman, L.R. and P.T. Hundemann, Regulatory Standards for Permits Under Section 404. Natural Resources and Environment, Vol. 7(1), pp. 12-14, 1992

Thompson, D.A. and T.G. Yocom, Uncertain Ground. Technology Review, Massachusetts Institute of Technology, pp. 20-29, August/September 1993

United States Army Corps of Engineers (USACOE), Corps of Engineers Wetlands Delineation Manual. Wetlands Research Program Technical Report Y-87-1, Vicksburg, MI, 1987


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