Attachment 3 Project Description.docx

Boone Fork Watershed Improvement Project 2018 – Project Description Brady Dodd, May 23, 2017/January 30, 2018/March 12, 2020 Project Background:

Boone Fork Stream Enhancement Boone Fork (Figure 1), in the Catawba River Basin, is classified by the state of NC as Class B, High Quality Water (HQW). The Boone Fork stream channel has been disturbed by past management in the area, including logging of the entire watershed to farming in the valley bottom. Up to three levels of historic channel elevations (terraces) were observed, indicating that at least three notable events scoured and deepened the Boone Fork channel within the last few centuries. Historically, it is suspected that streamflow had frequent access to its valley bottom floodplain with frequent wetland type habitat formed by abundant down woody debris and beaver activity. Currently, the channel is entrenched with short segments where a narrow floodplain bench is present. As a result stream banks are often tall, unstable and eroding. The occurrence of erosion increases in the downstream direction (see Photo 1).

FSR 2055 Drainage Improvements The FSR 2055 road runs parallel to the Boone Fork valley bottom. Several storm water drainage features send relatively large volumes of runoff from the road surface down the hill to the Boone Fork channel. Downstream from these features storm flows have scoured ephemeral channels and are sources of sediment to Boone Fork (photos 2-4).

FSR 6089 & 966 Drainage Improvements & Deep Cove Aquatic Organism Passage These system roads have had little attention through the years and maintenance is needed at stream crossings and where erosion has been extensive. Also, the FSR 6089/966 crosses Deep Cove with a squash pipe that is undersized and a barrier for passage of most aquatic organisms (photo 5).

Figure 1. Site location of Boone Fork Watershed Improvement Project.

Photo 1. Photo of Boone Fork, looking at eroded bank, May 11, 2017.

Photos 2-4. Erosion from FSR 2055 road runoff to Boone Fork.

Photo 5. Culvert on Deep Cove undersized and a barrier for passage of most aquatic organisms.

Project Description:

Boone Fork Stream Enhancement Within this stream reach, work is proposed to stabilize erosion and sources of sedimentation, improve aquatic habitat diversity, and improve floodplain access. This will be accomplished using natural channel design techniques including the construction of instream structures such as debris jams, log vanes and toe-wood revetment, detailed in Table 1 and Appendix A – Structure Specifications and Specifications Sheet. The channel’s natural dimension, pattern, and profile would be reestablished in the constructed reach using reference reach information to establish a stable stream channel with high quality aquatic habitat. See Attachment 1 for proposed changes to cross sections & longitudinal profiles.

Table 1. Proposed action description for Boone Fork Stream Enhancement.

Boone Fork Stream Enhancement Project 2020

General

Erosion control measures will be taken on all soil disturbed by the proposed work, including seed, mulch, and Coir matting on stream banks

FSR 2055 Drainage Improvements Stabilize scoured channels downstream from road drainage features including culvert outlets (photos 3 & 4) and locations of channel bottom instability (photo 2). Add three additional ditch relief culverts to the road to reduce stormflow reaching the unstable locations.

FSR 6089 & 966 Drainage Improvements & Deep Cove Aquatic Organism Passage On FSR 6089 stabilize the culvert outlet at the Benson Hollow crossing. On FSR 966 replace failing culvert with a ford or larger culvert on Raccoon Cove and stabilize sources of road failure and erosion further south on the road. Remove the FSR 6089/966 crossing on Deep Cove and replace it with a constructed natural bottom ford (see Specifications Sheet for detail). The Forest Service gate is located over the culvert, therefore that gate would need to be relocated closer to the junction with the main road (FSR 2055), and maintain closure of the gate to limit access across the ford to administrative use.

APPENDIX A – STRUCTURE SPECIFICATIONS

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