North Fork New River Watershed NC DWQ NEW RIVER BASIN PLAN: North Fork New River Watershed HUC 0505000101 2011 HUC 0505000101
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CHAPTER 1 North Fork New river watershed NC DWQ NEW RIVER BASIN PLAN: North Fork New River Watershed HUC 0505000101 2011 New River Watershed NC DWQ NEW RIVER BASIN PLAN: North Fork HUC 0505000101 Includes: Three Top Creek, Big Laurel Creek, Buffalo & Little Buffalo Creeks, Little & Big Horse Creeks & Helton Creek GeNeral watershed descriptioN watershed at a GlaNce This ten-digit hydrologic unit code (HUC) watershed, with an area of about 250 square miles, is the equivalent to DWQ’s old subbasin 05-07- couNties: 02 and contains the North Fork New River and its tributaries (See DWQ’s Ashe & Watagua Old Subbasins to New HUC Conversion map in the Maps Chapter). The majority of the watershed lies within Ashe County, with the headwaters MuNicipalities: of the North Fork New River beginning in Watauga County and the Lansing & West Jefferson headwaters of Big Horse Creek and Helton Creek beginning in Virginia. The North Fork New River flows in an east-northeast direction before it ecoreGioNs: converges with the South Fork New River to form the New River. Amphibolite Mountains, New River Plateau, Southern Crystaline The land cover within this watershed is mostly forested (80%) with Ridges and Mountains, & areas of agriculture (14%) and the least amount of developed land in Southern Sedimentary Ridges the New River basin (3.7%). Rural residential properties and pasture lands are scattered throughout this watershed. Agricultural activities perMitted Facilities: have historically consisted of pasture and cultivated croplands, but within NPDES WWTP: ........................6 the past 20 years has expanded to include Christmas tree farming. Major ...........................................0 The majority of agricultural lands in this watershed are found along Minor ...........................................6 streambanks. Non-Discharge Facilities: ..........3 Stormwater: ..............................2 Roughly 16,000 acres of conservation land are found in this watershed General .......................................2 Individual .....................................0 and include easements held by local watershed groups (Elk Knob State Animal Operations: ...................0 Park, Cherokee National Forest and Blue Ridge Rural Land Trust). populatioN: This watershed’s population is centered mostly around the towns of 2010: ................. Coming Soon Lansing and West Jefferson. Lansing’s population declined by 12% between 1990 and 2000, and was estimated to decline by another 2006 laNd cover: one percent by 2010 according to the 2000 census. West Jefferson’s Developed .........................3.81% population increased by 8% in 2000 and was estimated to increase by Forest ...............................81.1% another 12% by 2010. Agriculture .......................14.98% Wetlands ...........................0.11% 2001 Impervious Surface ..0.24% 1.1 FIgure 1-1: NoRth FoRk New River WAtershed (0505000101) hin Branch Bi Rips g Ho rs e D P C i B KB137 i x r n P o i e e g )"à «¬16 y o n e t L k C a C t a KB136 r o r u KB122 . e r "à C e ) e L )"à . r l i k ttl . C e H UV194 on R r o Helt C «¬93 e r )"à le F r e KB25 w e idd or KB63 s e k e k e k M HC )"à C )"à[ KB127 r ¡ KF5 N )"à ee k k KB121 r k O o P l r i d KB28 F o n F . F e ie d y l C )"à N g r n . i C r r a e o e R ¢¡ ALLEGHANY L )"à R k KB135 Lansing o i S *# c n t K7500000 h a g H g KF1 M g KB27 S i [ l KB33 ¡ h l i C )"à)"à )"à o C l r a l . l C s B r *# KB123 Cr ig e r . e L . l L e Litt au a KB125 )"à re u r k ¤£221 l el . C C r unda r re r KB118 Legend Ro b e e e C ou e k v )"à KB117 t k KB86 i C R )"à )"à x r. w L i Watershed Boundary Ne . n KB120 P oe*# *# ["à ork h )"à KB30 ¡) KF 22 Nort h F County Boundaries R KB31 oc Municipalities k «¬88 )"à KF 21 C )"¡[à )"à KB23 L )"à i ree KB29 KB134 tt Conservation Lands k le Jefferson rk ¡[ KF23 B o )"à u Primary Roads F f Bru sh KB119 *# f KB32 a *# "à )"à KB138 l )¡[ Bu o 88 NPDES Permits KF10 ffalo eek XY «¬*# T Cr C h r XY Major WW Discharge r . k e *# 18 KB26 e e *# e T Minor WW Discharge )"à KB141 r o C )"à p e Monitoring Sites C West p rk o r ¡¢ n Fo e Jefferson Ambient ki H s r e e o g k v ¡[ n H i Fish Community o R L ")à Benthos w e ASHE «¬16 N ¤£221 163 *# Hydrology - Use Support k UV r o Supporting F . N Impaired 0 1 2 4 6 8 *# No Data Miles WATAUGA 1.2 194 2 UV 2 NC DWQ NEW RIVER BASIN PLAN: NoRth FoRk N1 ew River WAtershed hUC 0505000101 2011 watershed water Quality overview The North Fork New River watershed has some of the best water quality in the basin and water quality has changed little in the five years since the last planning cycle. The large areas of forest and minimal agriculture and urban areas create only a minimal human impact to water quality. In DWQ’s efforts to protect the pristine nature of this watershed, a watershed-wide study was conducted to determine if these waters could be reclassified as High Quality Waters (HQW) or Outstanding Resource Waters (ORW). As a result, almost the entire watershed was reclassified as ORW. For a map of the affected area and a more detailed discussion see the Additional Studies section below. Little Buffalo Creek, near West Jefferson, is the only Impaired water body in the watershed and was not included in the reclassification. water Quality data summary For this watershed Monitoring stream flow, aquatic biology and chemical/physical parameters are a large part of the basinwide planning process. More detailed information about DWQ monitoring and the effects each parameter has on water quality is discussed in Chapters 2 and 3 of the Supplemental Guide to North Carolina’s Basinwide Planning document. UC 0505000101 2011 h ed h uNderstaNding the data ers t Biological & Ambient Rating Converted to Use Support Category A Biological (benthic and fish community) samples are given a W bioclassification/rating based on the data collected at the site FIgure 1-2: Use SuppoRt iver by DWQs Environmental Sciences Section (ESS). These CAtEgories FoR BIoLogical RAtingS R bioclassifications include Excellent, Good, Good-Fair, Not Biological Aquatic Life ew Ratings Use Support Impaired, Not Rated, Fair and Poor. For specific methodology N k defining how these rating are given see Benthic Standard Excellent R o Operating Procedures (SOP) or the Fish Community SOP. Good Supporting F Once a rating is given, it is then translated into a Use Support (Categories 1-2) Good-Fair th R Category (see Figure 1-2). Not Impaired o Not Rated Ambient monitoring data are analyzed based on the percent of Not Rated (Category 3) samples exceeding the state standard for individual parameters for each site within a two-year period. If a standard is exceeded Fair Impaired (Categories 4-5) in greater than 10.0% of samples taken for a particular parameter, Poor that stream segment is Impaired for that parameter. The fecal coliform bacteria parameter is the exception to the rule. See the Fecal Coliform Bacteria section in the Ambient Data portion below. For the purposes of this plan, any site with greater than 7.0% to 10.0% of samples not meeting a parameter’s standard will be considered Impacted. FIgure 1-3: ExAmple oF A Use Each biological parameter (benthic and fish community) and each SuppoRt and monitoring Box ambient parameter is assigned a Use Support Category based on its Use SuppoRt: iMpaired (14 mI) rating or percent exceedance. Definitions for each category can be 2008 IR Cat. 5 found in Use Support Methodology Chapter. Each monitored stream 2010 IR Cat. 5 segment is then given an overall category which reflects the highest individual parameter category. For example, using the data from Benthos (CB1) Fair (2008) Figure 1-3, the individual parameter categories would be as follows: NC DWQ NEW RIVER BASIN PLAN: N Benthos - 5, Fish Community - 1, Turbidity - 5. Therefore, the overall Fish Com (CF1) Good-Fair (2008) category, which is reported on the Integrated Report, would be 5 AMS Turbidity - 12% (Impaired). An Integrated Report is developed by the state every two (C1234500) FCB - 48% years and reported to the U.S. Environmental Protection Agency. 1.3 streaM Flow The basin experienced prolonged FIgure 1-4: Yearly AveragE FLoW RAtes (cfs) oF thE USgS gAgE droughts in 1998-2002 and 2007-2008 StAtIoN in thE New River Basin BEtween 1997 & 2008 and exceptionally high flows resulting USGS Flow Guage 03161000 - SF New River from the remnants of several hurricanes (Figure 1-4). During a three-week 700 period in September 2004, the tropical NC DWQ NEW RIVER BASIN PLAN: N 600 storm remnants of Hurricanes Frances, Ivan, and Jeanne lead to wide-spread 500 flooding throughout the central and 400 northern mountains in the Catawba, cfs French Broad, New, and Watauga 300 River basins. Rainfall estimates for 200 the combined three storms totaled more than 20-30 inches in certain 100 watersheds. Runoff from the storms produced flash floods throughout the 0 region, with peak flows in excess of 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 10,000 cfs (approximately 500 times Indicates periods of drought in the New River Basin median flows) in upper tributary streams; peaks flows in some tributary rivers exceeded 50,000 cfs.