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Home My WebLink About20011551 Ver 5_Monitoring Report_20130909The '01- 1 SS 1 Catena Grou 410 -B Millstone Drive p Hillsborough, NC 27278 (919) 732 -1300 September 5, 2013 NC DWQ, 401/Wetlands Unit 1650 Mail Service Center Raleigh, NC, 27699 -1650 Subject: Post Construction Monitoring Report #2, NCGC, Mount Airy, Surry County, North Carolina References: Permit No: SAW- 2011 -01765 The Catena Group, Inc. (Catena) has been retained by the North Carolina Granite Corporation (NCGC) to conduct post construction monitoring of the structures installed under the above referenced permit. Please find enclosed the Post Construction Monitoring Report #2 as required in Special Condition E of the 404 permit and Conditions 3 and 4 of the 401 Permit. Flow in the side channel and structure stability both meet permit requirements. The next monitoring period is scheduled for March of 2014. If we can provide any additional information or if you have any questions, please contact me at 919 - 732 -1300 (office) or 919 - 417 -8027 (mobile). Sincerely, The Catena Group, Inc. )&�WG. OL Michael G. Wood, NCLSS President Enclosures: Post Construction Monitoring Report #2 CC: Carlos Goad North Carolina Granite Corporation P.O. Box 151 Mount Airy, NC 27030 ROL99WR SEP - 9 2.013 VS �o ► 3 Y1 X001 O 1- 1 SS 1 Post Construction Monitoring Report #2 North Carolina Granite Corporation Hydrologic Flow and Function of Side Channel Monitoring In- Channel Structure Stability Monitoring Mt. Airy, North Carolina Prepared for: North Carolina Granite Corporation P.O. Box 151 Mount Airy, NC 27030 Tel: (336) 786 -5141 September 2013 Prepared by: &k4 The C at ena Group The Catena Group 410B Millstone Drive Hillsborough, NC 27278 Tel: (919) 732 -1300 S A Table of Contents 1.0 Introduction ........................................................................................... ............................... 1 2.0 Methodology .......................................................................................... ..............................1 2.1. Hydrologic Flow and Function of Side Channel Monitoring ........... ............................... 1 2.2. In- Channel Structure Stability Monitoring ....................................... ............................... 2 3.0 Results and Discussion ......................................................................... ............................... 2 Appendix A — Figures Appendix B — Photos Appendix C — Raw Data Sheets NCGC Monitoring Report #2 September 2013 Catena Job# 4159 Page i N 1.0 INTRODUCTION The North Carolina Granite Corporation (NCGC) received a 404 Permit (SAW- 2011- 01765) on September 5, 2012, and a 401 Permit (Certification No. 3936) on July 30, 2012, authorizing impact to 265 linear feet of the Ararat River through the placement of 1,680 cubic yards of granite to stabilize river banks while also deflecting flow toward the intake of the holding pond. In addition, after -the -fact authorization was given for an additional 600 cubic yards of permanent fill for river bank reconstruction. To maintain flow in a side channel, a 2 -inch PVC pipe was installed providing water from the Ararat River to the side channel. Both permits were modified in February 2013, to allow a closed inlet structure between the Ararat River and the holding pond. The 404 and 401 Permits both included Special Conditions that must be met for the permits to be valid. Specifically, Special Condition E of the 404 Permit and Condition 3 of the 401 Permit require that the side channel receiving the flow from the 2 -inch PVC pipe be monitored biannually, each February and August, for two years following construction of the stream structures. Hydrologic flow /function will be monitored to determine if the side channel still provides habitat for aquatic life propagation and maintains biological integrity — indicated by a measured flow of greater than 26,500 gallons /day. In addition, Condition 4 of the 401 Permit requires biannual monitoring of the in- channel structures to insure stability. 2.0 METHODOLOGY On August 30, 2013, Kate Montieth and Ivy Kimbrough of The Catena Group (Catena) monitored the site by walking the length of the side channel. Photos of the structures were taken at previously established photo stations to document current conditions (Appendix B). Z L Hydrologic Flow and Function of Side Channel Monitoring Flow, or stream discharge, in the side channel was measured at two locations (Appendix A: Figure 1) using a Global Water flow meter (Model FP111). Flow was calculated using the following formulas and measurements taken in the field: Flow (stream discharge) = Q Q = velocity (ft/sec) * area (t f) Area = width of stream (ft) * depth of stream (ft) At each location, stream width was divided into equal intervals and flow (velocity) was measured at each interval; raw data sheets are in Appendix C. Using the above formulas, flow was calculated for each location. NCGC Monitoring Report #2 Catena Job# 4159 September 2013 Page 1 2.2. In- Channel Structure Stability Monitoring The main channel of the Ararat River was walked from below the lower structure (double drop cross vane) upstream to the bridge over Linville Road (SR 1727). Structures were visually inspected from the bank and photos were taken at four photo points (Appendix A: Figure 1 and Appendix B). 3.0 RESULTS AND DISCUSSION Flow was measured at the lower and upper cross - sections (#I and #2 respectively) of the side channel. Flow at the upper cross - section ( #2) was measured at 36,804 gal/day. Water depths at the lower cross - section (# 1) were below the lower limits of the flow meter, so we were unable to obtain accurate measurements. Therefore, only the flow at the upper cross - section ( #2) is reported here with the assumption that downstream flow would be at a minimum equal to the upstream. Conditions of the permit require measured flow to be a minimum of 26,500 gal/day. Therefore, as of this second monitoring period, Special Conditions E and 3 have both been met. Overall, flow was lower than measured in March 2013, as is to be expected with the lower water levels often seen in the summer months. Construction of the in -stream structures was completed on March 15, 2013. Inspection of the structures during this monitoring period did not indicate any instability; therefore Condition 4 of the 401 Permit has been met. NCGC Monitoring Report #2 September 2013 Catena Job# 4159 Page 2 Appendix A: Figures NCGC Monitoring Report #2 September 2013 Catena Job# 4159 Page 3 Single Wing Deflector i, W -weir Double Drop Cross Vane 1 f. 4 Cross- Section #2 t Cross - Section #1 1. J Cross Section Location ® Photo Point Location Figure Date: The North Carolina September 2013 Granite Corporation Scale Catena Post- Construction Monitoring ° 40 eo Feet Group August 2013 Job No Surry County, North Carolina 4159 Appendix B: Photos NCGC Monitoring Report #2 September 2013 Catena Job# 4159 Page 5 Hydrologic Flow and Function of Side Channel Monitoring Photo Station 4: Side Channel enters Ararat at Photo Station 4: Looking downstream at side center of photo (yellow arrow) channel nexus with Ararat River Cross - Section 1 Side Channel upstream of Cross - Sections NCGC Monitoring Report #2 September 2013 Catena Job# 4159 Page 6 In- Channel Structure Stability Monitoring Photo Station 1: Looking Downstream at structures in Ararat from bridge over Linville Road (SR 1727) Photo Station 1: Looking Downstream at structures in Ararat from bridge over Linville Road (SR 1727) Photo Station 1: Looking Upstream Ararat from Photo Station 1: Looking Upstream Ararat from bridge over Linville Road (SR 1727) bridge over Linville Road (SR 1727) Photo Station 2: Single Wing Deflector Photo Station 2: NCGC intake structure with flood gate NCGC Monitoring Report #2 September 2013 Catena Job# 4159 Page 1 Photo Station 3: Installed W -weir. Photo Station 3: Installed Double Drop Cross Vane NCGC Monitoring Report #2 September 2013 Catena Job# 4159 Page 8 Appendix C: Raw Data Sheets NCGC Monitoring Report #2 September 2013 Catena Job# 4159 Page 10 Date: 9/ 3 61I Job:-4)59— nn Investiptors: Wetted width . WW 1—► depth d Now messurement WFUw"J width Site: X < Wetted Width (ft): ?_ Interval Width (ft): Death units (circle): Feet OR Inches Site: y, ' del G 1 Wetted Width (h). 4 Interval Width (ft): _ t Depth units (circle): Feet OR Inches ° 4- 1 1 2 3 4 S 6 1 7 a 9 10 De h d5 i 2 Veloc (ft /sec) `� 0 0 01 �? low �00 1 WFUw"J width Site: X < Wetted Width (ft): ?_ Interval Width (ft): Death units (circle): Feet OR Inches Site: y, ' del G 1 Wetted Width (h). 4 Interval Width (ft): _ t Depth units (circle): Feet OR Inches ° 4- rl t� 1 1 2 3 4 S 6 1 7 a 9 10 De h d5 i 2 Veloc (ft /sec) `� 0 0 01 �? rl t�