The Town of Huntsville

By

Briant H. Jacobs

Introduction

By mandate of the Division of Drinking Water Rules for Utah, every public municipality is required to have and implement a water source protection plan in order to ensure that their public culinary water is pure and safe from contamination. The Town of Huntsville has a water source protection plan that was initially completed by an engineering firm in May of 2001. The water source protection plan was updated in 2005 by state requirement. The update was not done by an engineering firm, but was completed by the Town sending representatives to meet with several landowners and various entities in the source protection area. The Town of Huntsville took the update as a time to determine if the Town could be more proactive to protect the Town’s collection springs.

The collection springs consist of three springs, one of which they share with a local monastery. The collection springs are located in an area that has an abundance of karst features and where sink holes are present. There is some indication that the surface water and the ground water could be interconnected in this region. If this is the case, the springs could be very vulnerable to pollution and the collection area will require the implementation of stricter codes from the Town of Huntsville. It is important to find out how sensitive the area is in the near future because recently there have been some land owners that have been considering developing portions of their land. If stricter land use regulations are needed, it will be easier to implement them before the land is developed. The majority of the land in the catchment area is currently used for dispersed livestock grazing, limited recreational activities, and a small amount of farming.

In order to assist the Town of Huntsville, this project was formed. The purpose of this project was to delineate the watershed contributing to the Bennett Springs collection area, to determine areas of vulnerability within the watershed collection area, to map the water rights within the catchment as well as in the surrounding areas, and to map land ownership within the collection area. ArcMap was used to accomplish these tasks.

Methodology

1-Watershed Delineation

The first thing that was done was to gather data in order to create a base map. This was accomplished by using ARGC and USGS. A NED (National Elevation Dataset) of the area was used as well as the nationally defined HUC 12 (Hydrologic Unit Code) catchments. Figure 1 depicts the catchment that is associated with the collection area of the Bennett Springs. The three Bennett Springs collection sites are depicted as the grouped triangles in Figure 1. By looking solely at the topographical features, the highlighted catchment area seen in Figure 1 is the only portion of the Pineview Subwatershed that would require more rigid protection regulations to protect the Town’s water.

Figure 1: Catchment Area in Question Based on Topology

The protection of the Town’s water does not come only from surface water, but also from the ground water. As stated in the introduction, the Town has some concern about karst features that could interconnect the surface water with the ground water. This type of interconnection could compromise the quality of the Town’s water.

New sinkholes have been appearing in the Sheep Herd Creek Valley which seems to correlate with peaking turbidity in collections from the Bennett Springs. Also, some of the farmers that have been in the area for awhile recall that some time ago tracer dyes were placed somewhere in the Sheep Herd Creek Valley which were found in the Bennett Springs. Documentation of this experiment cannot currently be found. These two events suggest that water is being transported from the Sheep Herd Creek Valley under the northern mountain ridge to the Bennett Springs. If this is the case, and it is suspected that it is, the catchments just south of the catchment area in Figure 1 should also be considered as an area in question as to increasing the protection regulations. Therefore Figure 2 depicts the revised area in question.

Figure 2 : Catchment Area Based on Topology and Events

Although the catchments that are considered contributors to the Bennett Springs were identified, not the entire area of the catchments could actually contribute to the collection sites. Because of this, two outlet points were added in order to run a Network Delineation so that the catchment area could be delineated. The two outlet points were added first by utilizing ArcCatalog in order to create a new shapefile in the working directory. The points were then physically added in ArcMap. The outlet points were selected along the stream network; one just above the Bennett Springs collection area, and the other was placed one river south of the first location. This was done while in an editing session. Figure 3 depicts the location of the outlet points.

Figure 3: Outlet Point Locations on the Stream Network

The watershed catchement area was then delineated by following the order of the tools under the Network Delineation tab from the TauDEM Toolbar. In short, the River Network Raster Upstream of the Outlets was created as well as the Stream Order Grid and Network Files, the Stream Shapefiles and the Watershed Grid. The Watershed Grid was converted to a shapefile and a Constant Drop Analysis was then performed. These steps created a delineated the catchment area that could potentially contribute to either one of the outlet points. This catchment area is depicted in Figure 4. The area that was clipped by doing the Network Delineation was only 1,738,039.18 meters² (0.67 miles²). Although this is not much area, it was area that did not contribute to the Bennett Springs.

Figure 4: Catchment Area of the Bennett Springs

Figure 4 depicts the delineated area in question where the implementation of more rigid regulations may be required.

The Town of Huntsville has a hand delineated map of the catchment area that was generated in May of 2001 by an engineering firm. The hand delineated map of the catchments was digitized and saved as a polygon shapefile in 2006. The delineated catchment area found by TauDEM, as seen in Figure 4, was compared to the digitized hand delineated catchment area. The hand delineated map was very similar, but it did differ in several areas. As the Town of Huntsville is trying to update their data and their maps of the Town, the TauDEM delineated catchments of these two points will prove to be more accurate and beneficial than their existing maps.

2-Vulnurable Areas

Based on topology, areas where the surface water is interconnected to the ground water could not be identified. The topology was only partially beneficial in determining the areas that contribute to the Bennett Springs. Subsurface delineation and flow paths were needed in order to determine the sensitive areas. ArcMAp could be used to create the desired subsurface layers, but only with drilling log data. After doing several searches on the internet and in the USU library for drilling logs of the catchment area, it was determined that none exist due to the rural-ness of the area. There are a fair number of wells, all of which have drilling logs, about 2 miles northwest of the catchments. The drilling logs for these wells was almost used and transferred to the area in question. With further speculation, it was concluded that the drilling logs were too far away from the area in question to be used for this purpose. The main reason being that the area in question is in a mountainous region and there would be many fragmented soil layers that would change the projected resultant layers.

A geological map of the area was found with hope that it would reveal some useful information. Figure 5 is a zoomed in portion of this map near the springs. By looking at the geological map of the area, the main thing that was really useful was the validation that the well logs should not be used as an accurate representation of the subsurface layers due to a major thrust fault line that runs through the catchment areas. There is also a normal fault that runs near the spring collection area. The major fault line is symbolized by the dark arrow heads that appear in a semicircle to the east of the spring collection point. The normal fault is symbolized as a bold line that terminates with a dot. On the geological map a red line runs from the Sheep Heard Valley towards the Bennett Springs collection area. This red line represents an anticline in the area. The presence of the faults and the anticline indicate that there could be major water routes between the different soil and rock layers. The map also indicates that the major layers in the region surrounding the Bennett Spring collection area are mainly composed of some type of limestone. The surrounding regions are noted as Qm, Mhl, Mhu, Mdo, and Mde. These were defined by use of a geological index as follows: Qm represents areas were mass movements have been deposited. Mhl is a layer equivalent to the lower Monroe Canyon Limestone. It is made up of Sandstone with limestone and dolomite interbeds. Mhu is roughly equivalent to the Monroe Canyon Limestone. It is Limestone with a sandstone bed near the base. Mdo is a doughnut formation that could be possibly equivalent to the Monroe Canyon Limestone. Mde is a Deseret Limestone which is made of limestone, dolomite and sandstone with phoshatic shale at its base (Utah Geological Survey). All of these layers have one thing in common: Limestone. Often water will pass through a limestone layer until it comes in contact with a second more impervious layer. The water will begin to pool above the second layer until it starts to translate along the division between the layers. As the water moves, it slowly erodes pathways or channels between the layers, facilitating additional flow. It is suspected, due to the variety of limestone in the region, that this is what has occurred in the area surrounding the Bennett Springs collection area.

In order to determine the subsurface water works of the proposed area, one of two things will need to be done. The Town of Huntsville will have to install and monitor observation wells near the Bennett Springs collection areas, or they will have to perform tracer dye tests. Either action should result in determining if the Sheep Herd Valley is interconnected to the Bennett Springs collection area. If they are connected, the flow rate between the two areas will be determinable as well as the vulnerability of the surround catchment area.

Figure 5: Zoomed in Portion of Geological Map

3-Water Rights

The Town of Huntsville wanted to know the location and quantity of water rights near and also inside the delineated catchment area. This aspect of the project also was facilitated using ArcMap. The water rights in the area were identified and their identification numbers were obtained from the Utah Division of Water Rights website. Each water right was then looked up by its identification number. By looking up the water rights individually, the location of diversion, the allotted amount of water for the right and the ownership were identified and noted. Within ArcMAp, a new layer for the water rights was created. The location, allotted water amount, and ownership were input into the created layer’s attribute table.

The location of the water right diversions are written based off of a quarter corner section or a township corner. High density quads were loaded into ArcMap, and the corner coordinates of townships within the catchment area were noted. The distances from the points of diversions were then converted from feet into meters, and then they were manipulated to reflect the projected coordinate system. By using the editor toolbar, the points of diversion were physically added to the base map. After adding all of the points of diversion from the catchment area, the symbology of the water rights layer was changed in order to identify the difference between wells and surface points of diversion. It should be noted that there were two surface diversion points that were different than the rest. One was a water right that granted limited water from only spring runoff, and the other was identified as “a surface diversion.” Not knowing why these two were different from the rest, they were symbolized apart from the others. Figure 6 shows the water rights within and near the catchment area. The shading of the area in Figure 6 creates a false sense for the topography, so the rivers were added for clarification.

Figure 6: Water Rights within the Vicinity of the Catchments

It was important to symbolize the different types of water rights in order to help the Town quickly identify the use of water in the area. The use of wells in the surrounding areas could drain the aquifer the Town uses and could potentially drastically draw it down. With a large potential for development in the area, this could become a greater concern in the near future.

4-Land Ownership

As previously stated, if, through additional studies, the catchment area is found to be vulnerable, the Town of Huntsville will need to implement strict regulations to maintain the Town’s water integrity. The residents of the Town will be notified through Huntsville’s monthly publications. Some of the land owners that will be affected, if this occurs, do not live within the Town and will also need to be notified. In order to easily identify all parties that would be directly affected, the Town requested that a map be created. This was done by obtaining the shapefiles from the Weber County Recorder’s Office. Two maps of the area were created depicting different features. One depicted land ownership with water rights and the other was just the land ownership. Figure 7 depicts the land ownership around the catchment area.

Figure 7: Land Ownership of the Catchment Area

Conclusion

Although this project did not resolve all of the concerns that the Town of Huntsville had with regard to their water collection system, it did generate some information and maps that will be useful to them. This project also identified the next step the Town should take to determine the vulnerability of the area. All of the derived shapefiles and raster data will be converted to and saved in both NAD ‘83 and the Utah State Plane coordinate systems. A geodatabase will be created to house each of the coordinate systems. The data will then be given to the Town of Huntsville for future use. The Town has a very basic version of ArcView and has said that they have not been successful in viewing layers with different coordinate systems at the same time. This has been a problem because they receive information from various sources which use different coordinate systems. With all the information saved in two different geodatabases, the Town will be able to add additional files to one of the goedatabses in the future.

Works Cited

ARGC. Utah.Gov. “NED and DOQ” 25 Oct. 2006. <http://agrc.utah.gov/agrc_>

Horizon Systems Corporation. “NHDPlus Points, Water bodies, Catchments, & Flow Lines.” 10 Nov. 2006. <http://www.horizon-systems.com/nhdplus/HSC-wth16.htm>

Town of Huntsville. Personal Contact. “Sources, Rough Watershed, Parcel Data.” 9 Nov. 2006.

USGS. NHD Geodatabase. “Watersheds.” 5 Nov. 2006. <http://nhdgeo.usgs.gov/viewer.htm>

USGS. Seamless Data Distribution. “Quads.” 28 Oct. 2006. <http://seamless.usgs.gov/website/seamless/viewer.php>

Utah Division of Water Rights. Utah.Gov. “Water Rights.” 17 Nov. 2006. <http://www.waterrights.utah.gov/>

Utah Geological Survey. Utah Department of Natural Resources. Progress Report Geologic Map of the Ogden 30’ X 60’ Quadrangle, Utah and Wyoming, Year 3 of 3. Feb. 2001. 14 Nov. 2006. <http://www.geology.utah.gov/maps/geomap/30x60/pdf/ofr-380.pdf>