Wetlands and Streams

CSG provides all forms of wetland services. From wetland assessments to mitigation design/build projects our biologists have over 26 years of experience meeting the wetland needs of clients so that their projects can move forward in regulated areas. In addition, we have a trained Professional Wetland Scientist (PWS) on staff.

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Wetlands and Streams

Wetland Assessment

In some cases, a client may wish to know about the presence of potential wetlands on a site without needing them delineated or specifically identified (e.g. when a land purchase is being considered). This is where a wetland assessment may be appropriate. Tasks in a wetland assessment include:

  • Acquire accurate property boundary maps/ surveys of subject site
  • Review off-site documentation, including NWI Maps, Soil Surveys, Aerial Photos, USGS Quad Maps and other recorded information
  • Perform Field Reconnaissance, including walking site to identify potential wetlands
  • Mark potential wetland areas in the field for later delineation, if desired by client
  • Compile assessment letter or report detailing findings for client

Wetland Delineation

CSG offers Wetland determination and delineation services pursuant to Section 404 of the 1972 Clean Water Act (including its regional supplements). CSG provides technical services associated with identifying wetland areas, delineation of wetland boundaries, and preparation and submittal of the Army Corps of Engineers Wetland Determination Data Forms for wetland boundary verification prior to land development.

Wetland Permitting/Violation Resolution

The physical alteration of water bodies in the United States, including wetlands and streams, are regulated by federal and state statutes under Section 401 (Certification) and Section 404 (Permits) of the Federal Clean Water Act.

CSG provides Section 404/401 stream and wetland permitting services to clients ranging from small site developers to large national corporations. CSG works closely with our clients and/or their engineers to develop site plans that meet the goals of the project while avoiding and minimizing negative impacts. This approach saves our clients time and money by expediting the permitting process and minimizing potential mitigation requirements.

The mitigation process depends heavily on the details of each situation and whether mitigation can take place on or off-site, but most involve:

  • Determine whether potential wetland impacts are avoidable
  • Invite regulatory agencies for a site visit to verify wetland delineation
  • Determine what type of permit is going to be required (based on size and quality of wetlands proposed to be impacted)
  • Army Corps’ 404 Individual Permit
  • Army Corps’ Nationwide Permit (all types)
  • Army Corps & IDEM Regional General Permit (RGP)
  • IDEM 401 Water Quality Certification (WQC)
  • IDEM Isolated Wetlands Permit
  • IDEM Combined 401 WQC and Isolated Wetlands Permit
  • Other Corps and IDEM combined permits or permits from other states or Corps Districts
  • Submit wetland delineation to appropriate regulatory agencies with application for permit to impact jurisdictional wetlands
  • A wetland permit application may require:
  • An alternatives analysis
  • Detailed engineering drawings and cross sections of wetland impacts
  • A list of affected landowners
  • Development of a mitigation plan complete with engineered plans and planting lists
  • Tract history
  • Possible additional meetings with regulators and/or landowners
  • Identification of off-site wetland mitigation sites and possible land acquisition
  • Identification of a wetland bank in the event that wetland credits can be purchased
  • Assist in the development of a required deed restriction for the new wetland

In addition, CSG has extensive experience obtaining After-The-Fact Permits for wetland and stream impact violation situations and providing Expert Witness Testimony related to wetland violations. CSG has a Professional Wetland Scientist (PWS) on staff.

Wetland Mitigation Design/Build

CSG can provide turn-key mitigation solutions for projects that impact wetlands and streams. Services provided by CSG include development of mitigation plans, stream and wetland restoration design, construction oversight and management, and wetland/stream mitigation installation. CSG has extensive experience constructing wetlands for mitigation purposes. Once the mitigation site has been identified, CSG can see the process through to completion. Construction of a wetland involves:

  • Evaluation of the soils at the potential mitigation site
  • Evaluation of the potential hydrologic characteristics and hydrologic modeling
  • CQA of the excavation subcontractor or wetland installation crew
  • Installation of the wetland seed mix, plant plugs or trees according to plan
  • Compilation of a completion letter to appropriate regulatory agencies

Wetland Monitoring

A required part of any 404/401/Isolated Wetland Permit is post-construction wetland/stream monitoring. Typically, a regulatory agency such as USACE or IDEM, will require a qualified biologist to inspect a mitigation site to determine its success according to criteria set forth in the permit. Monitoring typically involves inspection of the mitigation twice during the growing season and a report due at the end of the year documenting the results of the monitoring events. Wetland monitoring typically lasts for 5 to 10 years, depending on the type and size of the wetland mitigation. After the permitted monitoring period has been reached and the wetland has been deemed to meet or exceed the permit success criteria, CSG will seek to have the permit released by the regulatory agencies.

Monitoring of a wetland typically includes:

  • A site visit detailing the development of the wetland including a discussion of plant life, hydrologic characteristics, soil development and any wildlife observed
  • A site visit in the spring (June) and autumn (October) starting after the first growing season and any additional visits required by the regulatory agencies
  • An annual report detailing the wetland’s status (successful or unsuccessful)
  • A corrective action plan if the wetland is not functioning as expected
  • A letter requesting regulatory release of the permit once the wetland is deemed successful

Wetland Banking

Mitigation banking is the preservation, enhancement, restoration or creation of a wetland, stream, or habitat conservation area which offsets, or compensates for, expected adverse impacts to similar nearby ecosystems. The goal is to replace the exact function and value of the specific wetland habitats that would be adversely affected by a proposed activity or project.

Credits are units of exchange defined as the ecological value associated with converting to other economic uses a naturally occurring wetland or other specific habitat type. Mitigation credits to compensate for riparian impacts may be assigned in relation to the linear distance of a stream functioning at the highest possible capacity within the watershed of the bank.

Credits are designated by an interagency Mitigation Bank Review Team that evaluates and permits a proposed Mitigation Bank. The MBRT may include representatives of various federal, state and/or local government agencies, including: U.S. Army Corps of Engineers, US Fish and Wildlife Service, NRCS, IDEM (or environmental agencies from other states) and local soil conservation districts.

There are several advantages to drawing on mitigation bank credits. Mitigation banks usually provide greater benefits than on-site or small parcel mitigation efforts. Landowners PERC properties that are of higher ecological quality than the small parcel impacts they compensate for. Mitigation banks provide many functional business advantages, allowing for ease of development. They allow a developer to maximize the use of a preferred development site rather than breaking up the site into sub-optimal property uses. Because mitigation bank credits are negotiated prior to development, hence prior to impact, purchasing credits from a mitigation bank decreases permitting time and eliminate the need for monitoring. Both regulatory and long term management risk is passed from developer to mitigation banker.

Establishing a wetland/stream mitigation bank is difficult, time consuming and can be expensive. CSG’s biologists and engineers can work with a client to set up a wetland/stream mitigation bank in a developing watershed.

Non-Regulatory Educational/Aesthetic Wetlands

CSG biologists have extensive experience designing and installing wetlands and natural areas that are not required for mitigations or permits. Often, a school, park or educational institution wants to install a wetland for wildlife habitat enhancement, environmental education purposes or just aesthetics. CSG sometimes can combine these needs with a wetland mitigation, if conditions and timing allow.

Treatment Wetlands

Natural wetland systems have often been described as the “earth’s kidneys” because they filter pollutants from water that flows through on its way to receiving lakes, streams and oceans. Because these systems can improve water quality, engineers and scientists construct systems that replicate the functions of natural wetlands. Constructed wetlands are treatment systems that use natural processes involving wetland vegetation, soils, and their associated microbial assemblages to improve water quality. CSG has experience designing, permitting and installing treatment wetlands to treat pollutants such as sewage, storm water and landfill leachate.

Stream Assessments

Stream assessments are performed for a variety of reasons, including assigning priorities among many streams that are affected by upland development and developing information needed for restoration activities. There are a wide range of physical and biological assessment procedures and protocols including those used by the USEPA, USACE and individual state agencies.. CSG biologists can provide comprehensive stream assessment services, including erosion analysis and stream quality characterization.

Stream Impact Permitting

Similar to wetland permitting, CSG provides Section 404/401 stream permitting services to clients ranging from small site developers to large national corporations where stream impacts are needed. CSG works closely with our clients and/or their engineers to develop site plans that meet the goals of the project while avoiding and minimizing negative impacts. This approach saves our clients time and money by expediting the permitting process and minimizing potential mitigation requirements.

Stream Mitigation Design/Build

CSG emphasizes natural stream assessment and design principles. Our key personnel have attended the series of courses on Natural Channel Design from North Carolina State University and seek to restore the ecological and hydrological character of streams with a minimum of ‘hard’ bank armoring. Our biologists and engineers have extensive experience designing and installing new streams, stream relocations and stream enhancement features.

HHEI/QHEI Evaluations

Biologists at CSG have extensive experience using the Headwaters Habitat Evaluation Index (HHEI) and Qualitative Habitat Evaluation Index (QHEI) metrics to assess stream quality for use in permitting and mitigation.

Benthic Macroinvertebrate Studies

CSG biologists can performs analysis of semi-quantitative, quantitative, and qualitative benthic macroinvertebrate samples to calculate a variety of biotic index values depending on client needs and study objectives. Data may be used to meet the requirements of EPA Rapid Bioassessment Protocol III, specific state regulatory agency protocols, or client-specified study objectives.

Riparian Restoration

Riparian areas (the zone of land immediately surrounding or bordering a body of water) are an important part of water quality and aquatic habitat. As such, they are often a key part of waterbody (wetland and stream) permitting activities. CSG has extensive experience designing and installing riparian areas in conjunction with mitigation activities or stream and upland natural area enhancement.


Bioengineering is the term used to describe the use of plant and natural material to arrest and prevent slope and streambank failure and erosion. Bioengineering features are also used in in-stream structures such as J-Hooks and Vanes. The plant parts themselves, (roots and stems) serve as structural and mechanical elements in a slope protection system. Live cuttings and rooted plants are embedded in the ground in various ways to serve as soil reinforcements. Once established, the living material controls erosion by binding the soil with its root system. In-stream features help to direct water away from an eroding slope or sheer face so that natural vegetation can take hold to provide permanent protection. CSG has experience designing and installing bioengineering techniques such as live stakes, wattles, J-hooks, bendway weirs, cross vanes, vegetated coir logs and other commonly-used bioengineering techniques.

Expert Witness Testimony

Senior Ecologist and Professional Wetland Scientist, Greg Gerke, can provide expert witness testimony on behalf of Clients that be navigating an enforcement action and/or litigation pertaining to the Clean Water Act as regulated by the USACE.