Projects

Little Catoctin Creek TMDL Stream Restoration

The Maryland State Highway Administration (MDOT SHA) Office of Environmental Design (OED) restored approximately 3,063 linear feet of Little Catoctin Creek, located approximately 0.3 miles east of the MD Route 17 and U.S. Route 340 interchange in Knoxville, Frederick County as part of its efforts to meet the Total Maximum Daily Load (TMDL) reduction goals for sediment and nutrients. Coastal Resources, Inc. (CRI) worked with a prime consultant to design the erosion and sediment control plan, and perform the associated calculations, reporting, and permitting to accompany the design. CRI also coordinated environmental permit approvals and provided designated specialist services for the construction of the project.

The overall design approach was to utilize stream and floodplain restoration to create an ecologically diverse valley bottom ecosystem which maintains stability through native wetland vegetation and provides greatly increased sediment and nutrient processing. The Limit of Disturbance (LOD) of the project was 12.54 acres. The Sediment Stormwater Guidelines and Procedures, Maryland State Highway Administration (February 20, 2015) were used to develop the erosion and sediment control plans. While the project created a disturbance greater than 5,000 sf, it did not involve any land use changes or have any proposed increase in impervious surface. Because of this, there was no runoff reduction of impervious area and no opportunity to implement environmental site design (ESD) planning techniques and practices to the maximum extent possible (MEP). Stormwater management was not required.

Erosion and sediment control practices/techniques were implemented during the construction phase of the project to ensure that no contaminated runoff entered the waterways of Little Catoctin Creek. To minimize the amount of sediment laden runoff created, the new channel was graded in stages (from downstream to upstream) while flow was maintained in the existing channel. Once a portion of the new channel was stabilized, the flow was directed into the new channel via a fabric-based channel diversion to allow a portion of the existing channel to be filled and the adjacent floodplain to be graded and stabilized with matting. Pump-around practices were used to allow clean flow to bypass while the fabric-based diversions were being constructed at the project limits, to filter any contaminated water via filter bags. The 2011 Maryland Standards and Specifications for Soil and Erosion Control were used to design perimeter controls and other sediment control devices. A total of 7 different stream phases were outlined in the Sequence of Construction to minimize the amount of floodplain and stream work that was left unstabilized at any one time.

CRI prepared erosion and sediment control plans, special provisions, natural resources mapping, and a Stormwater Management and Erosion and Sediment Control Report that was submitted to MDOT SHA’s Plan Review Division (delegated authority from Maryland Department of the Environment). CRI submitted Concept, Site Development, and Final submissions and addressed comments at each submittal phase. CRI also coordinated closely with the stream designers and responded to comments pertaining to the E&S design during the MDOT SHA Milestone reviews.

Plan Sheet

Permitting activities by CRI included completing the Joint Federal State Permit Application Package for wetland and waterway impacts; completing the forest conservation exemption package; coordinating the project with the regulatory agencies, coordination with designers; request/coordinate support activities (stream/system studies, NEPA/MEPA, natural resource inventories); and obtaining environmental permit approvals.

During construction, CRI provided designated specialist services to ensure the contractor was accurately interpreting the design intent and building the project to meet that intent. The Designated Specialist (DS) was on site 3 days a week and provided daily reports detailing the construction progress and photos of daily activities. The DS was available to clarify the design plans when needed and answer any contractor questions during construction. CRI coordinated with the MDOT SHA inspectors, designers, and contractor to assist in the project’s successful construction.

Location:

Frederick County, MD

Client:

MDOT State Highway Administration – Water Programs Division

Key Services:

  • Wetland and Waterway Permitting
  • Erosion and Sediment Control Design
  • SHA Plan Review Division Permitting
  • Designated Specialist Services
Report Cover