Indian & Howard's Creek Local Watershed Plan

Indian Creek and Howard’s Creek Local Watershed Plan Preliminary Findings Report December 2008 This document was prepared by Mike Herrmann, NC EEP Watershed Planner. Cover Photo: Lower Indian Creek. i TABLE OF CONTENTS SECTION TITLE Page Section I. Introduction 1 Section II. Study Area Description 2 Section III. Study Area Ecological Assets 10 Section IV. Study Area Ecological Stressors 15 Section V. Existing Monitoring Information 20 Section VI. Preliminary Assessment of Watershed Functions 21 Section VII. Existing Watershed Protections and Policies 27 Section VIII. Identification of Data Gaps 29 Section IX. Future Assessment Strategies 30 Section X. Stakeholder Involvement 33 Section XII. Conclusions 36 Section XII. References 37 Appendix A. Methods to Develop Land Cover 39 Appendix B. Land Cover Statistics by Subwatershed. 42 Appendix C. NC DWQ Existing Monitoring Report 43 Appendix D. NC DWQ Draft Monitoring Plan 81 Appendix E. Functional Ratings for Subwatersheds 93 Appendix F. Stakeholder Group Participants 94 ii SECTION I. INTRODUCTION North Carolina’s Ecosystem Enhancement Program (EEP) mitigates for unavoidable impacts to the State’s streams and wetlands. This responsibility requires that EEP implement high-quality, cost-effective projects to compensate for those streams and wetlands lost or damaged in impacts from transportation and development. EEP chooses to implement compensatory mitigation projects using a watershed planning approach that involves stakeholder input, monitoring, fieldwork, and data analysis. These various sources of information are used to identify, assess, and prioritize projects that will provide EEP with the best opportunities to successfully protect and improve stream and wetland functions. In early 2008, EEP selected the Indian and Howard’s Creek watersheds (see Figure 1) in which to implement a detailed planning approach, or Local Watershed Plan (LWP), to identify opportunities to protect and restore streams and wetlands. These watersheds were selected based on a number of criteria and factors that include: • Opportunity to restore streams and wetlands; • Willingness of local resource professionals to protect and restore environmental resources; • Presence of drinking water intakes for Cherryville and Lincolnton; and • Impaired biological conditions in lower Indian Creek. The State’s Division of Water Quality (DWQ) classifies both Indian and Howard’s Creek as Class C waters, meaning they should support aquatic life propagation and protection along with secondary recreation. In 2006, “Fair” biological ratings in lower Indian Creek resulted in DWQ listing it as impaired along the creek’s mainstem downstream of Cherryville to its terminus at the Catawba River’s South Fork for not supporting its Class C uses. Upstream of Cherryville, Indian Creek is further classified as a Water Supply II watershed and supports its designated uses. In the adjacent Howard’s Creek, preliminary survey of GIS data and on-the-ground tours of the watershed identified a number of stream and wetland improvement opportunities that justified its inclusion in the LWP. Other than these factors, EEP’s justification to fund the watershed plan arose when the Program received authorization from its Policy Advisory Committee to implement projects in South Fork Catawba River Catalog Unit (CU 03050102) as mitigation for impacts occurring downstream in CU (03050103) (see Figure 1). Normally impacts must be mitigated within the same CU in which they occur. EEP, however, requested this authorization to allow the program to meet the challenging mitigation needs of 03050103, which includes the Charlotte Metropolitan area. This document, the Preliminary Findings Report, provides a summary of the first phase of EEP’s three-phase planning process. In this report, a review is provided of environmental stressors and assets, watershed functions, and data gaps. Consequently, this report forms the foundation for planning, monitoring, and fieldwork that will occur in later phases of the LWP process. For more information on EEP’s watershed planning, please visit the Program’s website (http://www.nceep.net/pages/lwpguide.htm). 1 SECTION II. STUDY AREA DESCRIPTION Indian Creek, Hydrologic Unit (HU) 03050102050010, and Howard’s Creek, HU 03050102040040, are located in North Carolina’s western Piedmont. The watersheds drain to the South Fork of the Catawba River, which flows to the main stem of the Catawba River at Lake Wylie. A small hydrologic-unit, referred to in this document as Middle South Fork (HU 03050102040030), hydrologically connects Howard’s Creek to Indian Creek. These three creeks collectively constitute EEP’s Indian and Howard’s Creek LWP (see Figure 1). The Cities of Lincolnton and Cherryville lay on the eastern and southern boundary of the watershed respectively. The two communities draw their drinking water within the LWP area. Generally, the creeks flow from northwest to southeast. Indian Creek watershed, the larger watershed, starts in Catawba County, continues south into Lincoln and Gaston County before turning east and emptying into the South Fork of the Catawba River. Table 1 provides area statistics for HUs by County in the LWP. Table 1. HU Area Statistics for the LWP Area Area HU Name HUCODE County Name (Mi2) (%) Indian Creek 03050102050010 Catawba 2.0 3% Lincoln 60.1 80% Gaston 12.9 17% HU Total 75.0 100% Howard's Creek 03050102040040 Catawba 4.2 12% Lincoln 29.7 88% HU Total 33.9 100% Middle South Fork 03050102040030 Lincoln / HU Total 5.3 100% LWP Total 114.2 100% Hydrology The LWP contains over 300 miles of mapped streams. Major tributaries to Indian Creek include Leonard Creek, Lick Fork, Little Creek, Little Indian Creek, and Mill Creek. Major tributaries to Howard’s Creek include Rockdam Creek and Tanyard Creek. There are no major tributaries in the Middle South Fork, but the HU has a number of unnamed tributaries draining to the South Fork River. Figure 1 provides a map that details the watersheds and tributaries in the LWP area. The National Hydrologic Dataset (NHD) (USGS 2000) 1:24,000 streams were examined as the base stream layer for the project. Stream data review with high-resolution 2005 aerial imagery revealed that a number of headwater tributaries were not mapped in the NHD. These typically had a drainage area between 20 and 100 acres and, when viewed over high-resolution imagery, possessed visible evidence of a stream channel. Based on the project’s need to identify headwaters for restoration and preservation purposes, the NHD stream file was edited to achieve three goals: 1) Add missing stream segments; 2) Relocate erroneously mapped streams; and 3) Remove missing streams. 2 SC NC Figure 1. Local Watershed Planning Area 3 Edits to the stream file were made using aerial photography and four foot contour lines published by the North Carolina (NC) Department of Transportation (NC DOT 2007). Most commonly, streams were added to the file if aerials and topographic data suggested the presences of streams. In order to be added to the stream file, missing streams needed to be longer than 1,000 feet. In total, about 30 miles of streams were added to the stream file. Stream alignments were adjusted on many occasions using aerial imagery to better locate stream channels. Finally, in very few cases, streams were shortened or removed. Table 2 lists the final stream mileage estimates for the LWP watersheds. Table 2. Stream Miles for LWP Hydrologic Units. Stream Length % of LWP Watershed (mi) Total Indian Creek 206.2 66% Howard’s Creek 89.3 29% Middle-South Fork 17.7 6% LWP Total 313.2 100% Geology & Soils Topography in the LWP varies from rolling hills in the headwaters to flat floodplains as the creeks approach the South Fork. Elevation above mean sea level ranges from a high of over 1,300 feet to a low of 700 feet. According to the Lincoln County Soil Survey (USDA 1995), two geologic belts traverse the area; Inner Piedmont Belt and King’s Mountain Belt. The Inner Piedmont Belt consists of metamorphic rocks (i.e., gneiss, schist). The King’s Mountain belt includes metamorphic and metavolcanic rock including intrusions of granite in the southeast portion of the LWP area. One site of geological interest is found on Tanyard Creek, a tributary to Howard’s Creek. Here, a variety of outcrops can be found that are excellent examples of the lower Tallulah Falls Formation, a geologic layer of the Inner Piedmont. These outcrops create unique rock formations and fault lines along with a series of slick rock falls along the creek. It was also once the location of Warlick Mill, a former mill site (Mershchat et al. 2008). For the study of wetlands and hydrology, hydric soils are of particular interest as they are one of the criteria for identifying wetlands. The U.S. Department of Agriculture (USDA) is responsible for mapping soils for counties, including hydric soils. For the study area, Worsham (WoA) is a common hydric soil, found typically in depressions (USDA, 2008). Chewacla (ChA) and Riverview (RvA) are two other soil types commonly found in floodplains and depressions in this area. Though mapped as hydric, only those soils frequently flooded with a water table near the surface during the growing season are likely to meet hydric criteria. Table 3 lists the USDA hydric soil map units. An additional soil feature of interest is erodibility. Erodible soils can contribute to sediment pollution in streams and degrade aquatic habitat. In the LWP area, three of the four soil types whose properties are most susceptible to erosion

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