FINAL PROJECT FOR GEOGRAPHY 406: ADVANCED GIS

POTENTIAL SKI RESORT SITES IN THE RUBY MOUNTAINS, NEVADA

Introduction

The town of Elko, located in northeastern Nevada, offers a variety of recreational opportunities for visitors to the area. Opportunities exist throughout the region for mountain biking, horseback riding, cross-country skiing, snowmobiling, motorcycle riding, photography, nature study, rock climbing, fishing, hunting, camping, picnicking, water activities, viewing wildlife and wild horses. The majority of these recreational activities are accommodated by the nearby Ruby Mountains. Located 20 miles south of Elko, the Ruby Mountains are among the tallest and most biologically diverse mountain ranges in the state of Nevada. Rising rapidly from a base elevation of 5,600 feet, the Rubies feature 10 peaks above 10,000 feet, including 11,387-foot Ruby Dome. Due to their height and isolation, the Ruby Mountains get more precipitation than most basin and range mountains. Averaging an annual snowfall of 300 to 400 inches a year, the Ruby Mountains hold tremendous potential to produce premier ski resorts in an isolated and secluded environment. Because tourism plays such a vital role in Elko’s economy, the construction of a world class ski resort would greatly increase Elko’s attractiveness as a tourist destination for outdoor enthusiasts.

Purpose

The purpose of this project is to use Geographic Information Systems (GIS) to determine the potential for suitable ski resort locations in the Ruby Mountains. Various physical and environmental criteria will be utilized to conduct this suitability analysis.

Criteria

Five main criteria were used for this suitability analysis. These criteria include:

Slope - It is important to consider slope in any ski resort suitability study. Potential ski areas need to have a slope grade that is steep enough for skiers. Since the majority of skiers ski at an intermediate experience level, slopes between 25% and 45% were seen as the most suitable.

Aspect - Aspect is a very important factor when considering suitable locations for a ski resort. The aspect directly relates to the amount of direct incoming solar radiation, which affects both the quality and quantity of snow on the slopes. For the purpose of this study, areas with north, northeastern, and northwestern facing slopes were seen as the most suitable.

Elevation - Since the Ruby Mountains have a significant elevation range, elevations between 7,500 feet and 10,000 feet were seen as the most suitable.

Landcover - Areas that were covered predominately with evergreen or mixed forest were designated as suitable. This criteria was based largely on the aesthetic and visual value of trees. Skiers tend to prefer wooded areas as opposed to barren areas.

Distance from Roads: Transportation to and from resort areas is a key component of ski resort operation. Therefore, a distance from major roads criteria was incorporated into this analysis. Areas within 1 mile of a major road or highway were considered to be the most suitable for this study.

Data

Digital Elevation Models (DEM) were a significant portion of my project since, slope, aspect and elevation are key factors in determining ski resort site suitability. The DEM’s that were used consisted of 4 30-meter resolution quadrangles residing in the Ruby Mountain Range in the state of Nevada. The four quadrangles, Lamoille, Verdi Peak, Ruby Valley School, and Ruby Dome were downloaded from the California State University Northridge www.geogdata.csun.edu website. The landcover and roads data for this project was provided by the W.M. Keck Earth Sciences & Mining Research Information Center. This data resource is supplied by the University of Nevada Reno and can be found at http://keck.library.unr.edu.

Methodology

The analysis techniques used in this study utilized both raster and vector data.

RASTER ANALYSIS:

- Converted 4 SDTS quadrangles to digital elevation models (DEM’s).

- Mosaicked the four DEM’s into one combined DEM layer using the spatial analyst raster calculator.

- Derived slope and aspect layers from the combined DEM layer in spatial analyst.

- Slope, aspect and elevation layers were reclassified using the spatial analyst reclassify function.

- Converted slope, aspect, elevation and landcover raster layers to vector layers using the spatial analyst convert raster to features option.

VECTOR ANALYSIS:

- Combined the slope, aspect, elevation and landcover vector layers into one final vector layer using the geoprocessing wizard union layers option.

- Joined weights tables that were constructed for each individual variable to the combined vector layer attribute table with the join tables option.

- Created a new field in the combined vector attribute table and named it Total weights.

- Used the field calculator to sum the weights for the combined variables. This allowed for the identification of the areas that best met the set of criteria.

- Used the buffer wizard option to create a 1-mile buffer around the major roads layer.

- Used the select by locations option to select areas completely within the 1 – mile buffer.

Procedures

Step #1: Mosaic DEM’s

Four DEM’s

Combined DEM’s

Step #2: Derive slope, aspect and elevation layers from DEM

Main Criteria Layers

Slope Layer

Aspect Layer

Elevation Layer

Landcover Layer

Step #3: Reclassification

Elevation Layer

Slope Layer

Aspect Layer

Step #4: Conversion to Vector

Elevation Vector Layer

Slope Vector Layer

Aspect Vector Layer

LandCover Vector Layer

Step #5: Combine Vector Layers

Unioned Vector Layers

Step #6: Join Weights Tables

Weights Tables

The attributes in each table were weighted according to their importance. The attributes that best fit the selected criteria were given a weight of 4. Attributes that somewhat fit the selected criteria where given values of 2 and 3. Attributes that least fit the selected criteria were given a weight of 1. Attributes that were not applicable to this study were given a weight of -999. The most suitable locations will have a total weight of 16.

Elevation Weights Table

Slope Weights Table

Aspect Weights Table

Landcover Weights Table

Step #7: Calculate Total weights Map

The total weights values were simplified by creating a working classification field in the unioned vector layer attribute table. Values between 13 and 16 were given a value of 4 and considered to be the most suitable. Values between 9 and 12 were given an value of 3 and considered to be somewhat suitable. Values between 1 and 8 were given a value of 2 and considered least suitable. Values between 0 and -1996 were given a value of one and considered not suitable.

Step #8: Create a 1-Mile Buffer Around Major Roads

Only areas with a working classification value of 4 were considered when looking for locations within 1 – mile of major roads.

Step #9: Create the Final Map

Results

Red Areas indicate locations that are the most suitable for the construction of a ski resort. The siting of these areas was based solely on the criteria chosen for this study.

Conclusion

There were as number of sites that I found to be suitable. According to my criteria, the best sites for a potential ski area reside toward the mouth of Lamoille canyon in the Northwest region of my study area as well as the very end of Lamoille Canyon. All of these areas are within 1 mile of Nevada State highway 227. Although these areas fell within my weighted criteria, it is possible that these locations still might not be suitable for a potential ski area. Other factors such as proximity to an energy source, cost of building access roads, and finding an appropriate place to build a ski lodge could hinder the site selection process in these areas. Based purely on a weighted suitability study of my criteria and thorough GIS analysis, these areas hold the most potential for a possible ski resort site.