Compensatory mitigation sites are often retained by the DOT and maintained according to a management plan, or as needed, based on the monitoring report. Except for the plant establishment period and trash pickup, no maintenance activities take place in created wetlands unless otherwise stated in the management plan, the contingency plan for the wetland, or the wetland monitoring report. In most cases this restriction on maintenance activities also applies to the designed upland buffer around the wetland.

In wetland mitigation sites, some vegetation management may be performed in accordance with management or contingency plans for the site. Long-term maintenance required in the management plan may include: [N]

• Repairing damage to the site from vandalism, storms, or fire.
• Control of exotic and invasive weed species.
• Eradication of state-listed noxious weeds.
• Plant replacement, if necessary, to meet permitting requirements.
• Selective removal of some types of trees to facilitate the natural succession of desirable plant communities. This decision is made in conjunction with the DOT Biologist and Landscape Architect.
• Other activities required to maintain a functioning wetland as determined by the DOT environmental specialists.

Primary environmental stewardship practices for maintenance of wetlands include the following:[N]

• Develop a long-term maintenance plan with the cooperation of DOT Maintenance, Biologists, and Landscape Architects.
• Establish a feedback loop for typical maintenance problems that might arise specific to the selected site. Include the region's Environmental Office, the design Biologist, and the Landscape Architect in that loop.
• Wetland vegetation should not be sprayed, mowed, or cleared except when necessary to maintain designated roadside ditches or detention ponds.
• Designate herbicide restrictions near wetlands. Application of herbicides in wetland mitigation sites requires an aquatic certification on the applicator's license.

All emergency actions in or adjacent to streams, wetlands, lakes, ponds or other water bodies, or historic resources require some form of environmental review and notification to regulatory agencies and thus are coordinated through the environmental staff. Typical maintenance environmental stewardship practices in emergency situations include: [N]

• Written notification of emergency work includes a description of the proposed action; a location map and plan for the proposed project; and reasons why the situation is an emergency.
• Emergency projects that require authorization from the USACOE are coordinated appropriately.
• All emergency work should be performed to cause the least modification, disturbance, or damage to the course or bed of a stream and its banks, or any adjacent wetlands.
• No equipment should be operated in the water unless it has been approved by the state's Department of Environmental Conservation.
• When conducting emergency work, all general and special permit conditions should be followed.
• When significant project modifications occur during construction, such changes should be coordinated with environmental staff and/or the permitting agencies.