Precipitation, Streamflow and a Look at

Little Bear River Contaminants

Project Outline

Becky Goode

Introduction

Objectives

Study Area

Precipitation

Brook Demitropoulos

Streamflow

Comparing Precipitation and Streamflow

Bimayendra Shrestha

Contaminants in Little Bear River

Data Sources

Introduction

Figure 1 The Hydrologic Cycle

Water is in constant motion, whether it is dealing with a rainstorm, a raging stream or even evaporation. The movement and recycling of water makes up the hydrologic cycle, which plays a vital role in understanding water, as well as, how to properly manage water resources. As can be seen in Figure 1, there is a relationship between the different parts of the hydrologic cycle. For instance, precipitation can cause an increase in streamflow, whereas, evaporation leads to a decrease in streamflow.

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Objectives

The hydrologic cycle is made up of many different factors, as a result, it can become quite complicated when trying to analyze the relationships between those factors. In order to get a very generalized idea of some of these relationships, the process was greatly simplified. Precipitation and streamflow were the only factors that were taken into consideration which means that factors, such as, snow melt, infiltration and evaporation were not taken into account. It should be noted that in order to get a really accurate picture of this relationship all of these factors should be included, but in terms of this project things will be simplified.

The main objectives of this project are:

1. Compare precipitation data and streamflow data of weather stations and gauging stations, as well as, analyze the relationship that exists between these two factors through the use of runoff ratios.

2. Analyze contamination in the Little Bear River.

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Study Area

The study area used in this project is the Little Bear-Logan watershed. This watershed is mostly located in the northern part of Utah with a small portion that extends into southern Idaho. The watershed is approximately 800 km² in size. The Little Bear-Logan watershed has been designated as a Hydrologic Unit Area (HUA) for water quality improvement. Primary impacts to water quality include sediment loading from agriculture and accelerated stream bank erosion, nutrient loadings from livestock waste, and loss of stream and riparian habitat. Figure 2 shows the location of the Little Bear-Logan watershed in the state of Utah. The light blue line represents the outline of Cache County and indicates that the majority of the watershed is located within the boundaries of Cache County.

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Precipitation

The locations of the weather stations located in the Little Bear – Logan Watershed were found on the Western Region Climate Center website. These locations are shown in Table 1.

Table 1 Location of Weather Stations

STATION NAME	LONGITUDE	LATITUDE	LONGITUDE DD	LATITUDE DD
Logan Radio	111° 50' W	41° 46' N	-111.8333°	41.7667°
Logan Experiment Station	111° 49' W	41° 45' N	-111.8167°	41.75°
Logan USU	111° 49' W	41° 44' N	-111.8167°	41.7333°
Logan 5 SW	111° 54' W	41° 40' N	-111.9°	41.6667°
Hardware Ranch	111° 34' W	41° 36' N	-111.5667°	41.6°

Once the latitude and longitude coordinates for each station are converted into decimal degrees (DD), ArcMap was used to transfer the table to an event and then to a shape file. The resulting point shape file is shown in Figure 3, which indicates the locations of the weather stations in the watershed.

The precipitation data was also obtained from the Western Regional Climate Center website. Table 2 shows the long-term average monthly precipitation data (in.) for each of the five weather stations located in the Little Bear – Logan Watershed. Figure 4 is a graphical representation of the long-term average precipitation data for each month. The graphs show a little higher precipitation in the Spring months and lower precipitation in the Summer months. This is consistent with the climate of this area.

Table 2 Long-term Average Monthly Precipitation Data in inches

STATION NAME	JAN	FEB	MAR	APR	MAY	JUN	JUL	AUG	SEPT	OCT	NOV	DEC
Logan Radio	1.26	1.28	1.69	1.8	1.87	1.39	0.73	0.92	1.39	1.61	1.43	1.28
Logan Experiment Station	1.58	1.28	1.63	1.99	1.61	1.51	0.43	0.99	1.12	1.43	1.45	1.54
Logan USU	1.58	1.52	1.91	2.02	2.05	1.22	0.65	0.82	1.21	1.72	1.48	1.46
Logan 5 SW	1.7	1.66	1.83	1.94	2.12	1.32	0.88	0.92	1.34	1.94	1.58	1.51
Hardware Ranch	1.72	1.55	1.55	1.63	1.72	1.25	0.73	1	1.33	1.38	1.54	1.68

Figure 4 Long-term Average Monthly Precipitation

Due to the fact that the precipitation data is only for five specific points in the watershed, it is necessary to calculate the area average precipitation in order to obtain a better picture of the precipitation over the whole watershed. There are many different methods that can be used to accomplish this. For this project, two different methods were used and the results were analyzed to determine the best method for the study area.

The first method that was tested was the Thiessen method which is an allocation function based on distance. The thiessen method takes each point in the watershed and associates it with the nearest weather station, thus a thiessen polygon is formed for each weather station. This process is easily preformed in ArcMap by using Spatial Analyst/Distance/Allocation. It is important to make sure that before the Spatial Analyst is performed the options of the Spatial Analyst have been set to cover the domain of interest (for example the watershed). Upon completion of the Spatial Analyst a thiessen grid is formed (Figure 5).

The thiessen grid contains Object ID, Value, and Count in its attribute table. The Object ID corresponds to the FID in the weather station attribute table so these two tables can be easily joined. The Count attribute contains the number of grid cells in the watershed associated with each weather station. Once the two tables have been joined and exported, Excel can be used to help with the necessary area average precipitation calculations. The area average precipitation can be calculated using the following equation:

The area average precipitation was calculated for each month and the results can be seen in Table 3. Figure 6 shows a graphical representation of the new data.

Table 3 Area Average Precipitation for the Little Bear – Logan Watershed in inches

JAN	FEB	MAR	APR	MAY	JUN	JUL	AUG	SEPT	OCT	NOV	DEC
1.61	1.49	1.67	1.8	1.85	1.32	0.73	0.95	1.31	1.58	1.52	1.54

Figure 6 Monthly Area Average Precipitation (in.)

The main problem with the Thiessen method is that elevation is not taken into account. The Little Bear – Logan watershed is located in an area that is made up of mountains and valleys, as a result, these factors need to be considered in the calculations. The second method that was tested was the Hypsometric method which develops a relationship between precipitation and elevation. The Spatial Analyst/Zonal Statistics function can be used to associate elevation values with precipitation values from each weather station. Once the Spatial Analyst for the Hypsometric method is finished a table is produced that contains the elevation associated with each weather station. This table is then exported to Excel where a relationship between total precipitation and one of the fields representing elevation is developed. The raster calculator in ArcMap can then be used to apply this relationship over the whole watershed. Figures 7 and 8 show the resulting relationship.

Figure 7 Relationship between Precipitation and Elevation

From Figure 7, it can be seen that there is a problem because the trend line is sloping in the wrong direction. According to the graph, there is lower precipitation at higher elevations. Figure 8 also shows that there is more precipitation in the valleys and less precipitation in the mountains. In reality, there should generally be higher precipitation at higher elevations. The problem with the hypsometric method is caused by the fact that the weather stations are not spread out over the watershed. Figure 8 shows that four of the five weather stations are located in the valley and Figure 7 indicates that those same four weather stations have similar elevations. As a result, an accurate relationship between precipitation and elevation can not be determined. It has been shown that both methods have their problems. The problem with the hypsometric method, however, is caused by insufficient data due to the fact that the weather stations do not completely represent the whole watershed. Given all of these factors, the thiessen method was selected for the project with the understanding that it is not completely representative of this given study area.

There is a lot of future work that could be done involving the precipitation data to obtain a more accurate picture of the Little Bear – Logan watershed. The main problem with the data is that it is not a very good representation of the whole watershed. This is mainly due to the fact that the majority of the weather stations are located in one little area. In order to solve this problem it will be necessary to obtain more data, especially data associated with some of the higher elevations in the watershed. If better data could be gathered, then the hypsometric method could be used to develop a more accurate representation of the area average precipitation.

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Streamflow

From the USGS website and by clicking on the link Statewide Streamflow Table, the menu at the top of the page can sort the data by hydrologic unit. The Little Bear-Logan hydrologic unit is shown along with the three gauging stations. Each individual gauging station can then be selected. The locations of the gauging stations were shown on the station home page. This information was collected and compiled as shown in Table 4.

Table 4. Streamflow Gauging Stations

Stat No.	Name	Latitude	Longitude	Drainage Area
10105900	Little Bear River at Paradise, UT	41°34'32"	111°51'16"	182 miles²
10109000	Logan River Above State Dam, Near Logan UT	41°44'36"	111°46'55"	214 miles²
10113500	Blacksmith Fork AB U.P. & L CO, S Dam NR Hyrum	41°37'25"	111°44'17"	263 miles²

The next step was to convert the station coordinates from latitude and longitude into decimal degrees.

This can be done by taking the degrees + (minutes / 60) + (seconds / 3600). The resulting calculations are shown in Table 5.

Table 5. Station Coordinates in Decimal Degrees

Stat No.	Name	LatDD	LongDD
10105900	Little Bear River at Paradise, UT	41.5756	-111.854
10109000	Logan River Above State Dam, Near Logan UT	41.7433	-111.782
10113500	Blacksmith Fork AB U.P. & L CO, S Dam NR Hyrum	41.6236	-111.738

By using Excel and saving the file as a .dbf file, the file can be opened in Arc Map. The table can be transferred into an Event. Then the data can be exported as a shape file. The points of the gauging stations were plotted on the map of the Little Bear-Logan watershed as shown in Figure 9.

The three stations are located on the three main rivers on the watershed; one is on the Logan River, another is at Blacksmith Fork near Hyrum, and the last station is on the Little Bear River. They are fairly close to each other and not spread out over the whole watershed. Therefore, this does not display a completely accurate picture of the streamflow over the whole watershed. Unfortunately, this was the only data that was available for the project area.

From the USGS website, a wide range of streamflow data could be collected. From the drop down menus, one could select daily streamflow, monthly streamflow, annual streamflow, the station home page, the station site map, and recent daily information. To begin, the focus was placed on the daily streamflow at each station. Figure 10 shows the streamflow based on 83 years of record.

Figure 10 Daily Streamflow

The next step was to look at the average annual streamflow. From the three stations, the average monthly streamflow was taken for the year 2000. Table 6 and Figure 11 show the results of these calculations.

Table 6 Monthly Streamflow for the year 2000

Station No.	Jan	Feb	Mar	April	May	June	July	Aug	Sept	Oct	Nov	Dec
10092700	1,091	953	1,008	801	644	726	821	764	491	439	463	411
10105900	57.5	65	72.5	111	91.2	19.1	18.6	18.4	26.6	31.8	37.9	38.8
10109000	129	121	125	226	402	278	146	113	101	106	113	100
10113500				131	116	96.8	87.5	86.3	73.4	76.4	73.1	70.1

Figure 11

In order to compare the streamflow data with the precipitation data, the information would need to be considered over a longer period of time. Therefore, the long time average streamflow was collected and displayed in Table 7. Figure 12 graphically shows the data from Table 7.

Table 7 Long-time average monthly streamflow (cfs)

Station No.	Jan	Feb	March	April	May	June	July	Aug	Sept	Oct	Nov	Dec
10105900	53.4	57	121	230	348	161	40.1	33.9	39.8	49.1	50.6	49.3
10109000	80	79.4	99.8	201	490	564	246	132	109	100	95	85.2
10113500	78.7	81.5	103	216	296	172	122	107	97	92.9	87.3	82.4

Figure 12 Long-time Average Monthly Streamflow (cfs)

The units of streamflow were cubic feet per second. The precipitation data was collected in inches. By using the equation:

After converting the streamflow into inches, Table # was produced.

Table 8. Long time average streamflow (inches)

Station No.	Jan	Feb	March	April	May	June	July	Aug	Sept	Oct	Nov	Dec
10105900	0.338	0.326	0.766	1.410	2.204	0.987	0.254	0.215	0.244	0.311	0.310	0.312
10109000	0.431	0.386	0.538	1.048	2.640	2.940	1.325	0.711	0.568	0.539	0.495	0.459
10113500	0.345	0.323	0.452	0.916	1.298	0.730	0.535	0.469	0.411	0.407	0.370	0.361

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Comparing Precipitation and Streamflow

The precipitation data was already in the units of inches and now having converted the streamflow into inches, the data can be compared. Table 9 shows the average precipitation along with the streamflows for each gauging station.

Table 9 Average Precipitation and Streamflow

Stations	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sept	Oct	Nov	Dec
Average Precipitation	1.61	1.49	1.67	1.80	1.85	1.32	0.73	0.95	1.31	1.58	1.52	1.54
10105900	0.338	0.326	0.766	1.41	2.204	0.987	0.254	0.215	0.244	0.311	0.31	0.312
10109000	0.431	0.386	0.538	1.048	2.64	2.94	1.325	0.711	0.568	0.539	0.495	0.459
10113500	0.345	0.323	0.452	0.916	1.298	0.73	0.535	0.469	0.411	0.407	0.37	0.361

Figure 13 was produced in Excel using the data from Table #. These lines follow a similar path. When there is precipitation, the streamflow is increasing. When there is no precipitation, the streamflow decreases, as expected. Snow fall and infiltration are not taken into consideration with the data. If these two factors are calculated in, then the data will be more accurate.

Figure 13 Precipitation and Streamflow

With the data collected, runoff ratios can then be calculated. A runoff ratio equals the average yearly streamflow divided by the average yearly precipitation. The average yearly precipitation was calculated to be 17.37 inches. The average yearly streamflow for each gauging station is shown in Table 10 below.

Table 10 Average Yearly Streamflow

	Average Yearly Streamflow (in)
Little Bear River at Paradise UT	7.677
Logan River Above State Dam	12.08
Blacksmith Fork Near Hyrum UT	6.617

The runoff ratios were calculated to be: 0.4420 for Little Bear River at Paradise UT

0.6955 for Logan River above State Dam

0.3809 for Blacksmith Fork near Hyrum UT

“The runoff ratios are important to society due to the fact that they show the effect that fluctuations in climate have on hydrologic conditions, such as floods, droughts, and the seasonal distribution of water supplies within a region….By examining such records, we can better understand hydrologic responses to those conditions and anticipate the effects of postulated changes in current climate regimes” (Landwehr, Lumb, and Slack).

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Contaminants in Little Bear River

Fig 14 Location of Little Bear River

Introduction

Water Quality Standards consist of use designations, numeric standards, narrative standards, anti-degradation policy and criteria necessary to protect the uses. The designated beneficial use assigned to the Little Bear River and/or its tributaries include 2A, 2B, 3A, 3D, 4. Such a classification system is developed by EPA. It sets the Total Maximum Daily Load (TMDL) of each pollutant for these designated beneficial uses of the water bodies. The goal for the TMDL is to meet state water quality standards for the designated and beneficial uses of the waterbody.

Table 11 State Beneficial Use Classification and Description

Class 1	Protected for use as a raw water source for domestic water systems.
	Class 1C: Protected for domestic purposes with prior treatment by treatment processes as
	Required by the Utah Division of Drinking Water.
Class 2	Recreational use and aesthetic
	Class 2A: Protected for primary contact recreation such as swimming.
	Class 2B: Protected for secondary contact recreation such as boating, wading, or similar uses.
Class 3	Protected for use by aquatic wildlife.
	Class 3A: Protected for cold water species of game fish and other cold water aquatic life,
	Including the necessary aquatic organisms in their food chain.
	Class 3B: Protected for warm water species of game fish and other warm water aquatic life,
	Including the necessary aquatic organisms in their food chain.
	Class 3C: Protected for non-game fish and other aquatic life, including the necessary aquatic
	organisms in their food chain.
	Class 3D: Protected for waterfowl, shore birds and other water-oriented wildlife not included in
	Classes 3A, 3B, or 3C, including the necessary aquatic organisms in their food chain.
	Class 3E: Severely habitat-limited waters. Narrative standards will be applied to protect these
	waters for aquatic wildlife.
Class 4	Protected for agricultural uses including irrigation of crops and stock watering.
Class 5	The Great Salt Lake. Protected for primary and secondary contact recreation, aquatic wildlife,
	and mineral extraction.

The Little Bear River has two main drainages. The South Fork that drains the Wellsville Mountains and the Bear River Range. There is a dam Porcupine Reservoir and other at the Hyrum Reservoir.

Little Bear River Watershed is located in Cache County, Northern Utah. The watershed is mostly used for agriculture purpose which includes cropland, pasture and rangeland. The national forest and state lands are used for grazing and forest areas. About 11% of the land is irrigated.

Fig 15 Land Ownership

Impairments of Water Quality

The state has assigned a specific concentration for water quality indicators phosphorus and total suspended solids for different uses. The concentration measured at a particular site must also take into account the flow in the river. A seasonal TMDL can be used which would require increased monitoring. In this study, the median flow was used. Also Input from a point source does not vary with flow. But non-point source input- such as sediments carried by runoff- is highest during high flow runoff periods.

Table 12 State water quality pollution indicator values

PARAMETER	Recreation & Aesthetics		Aquatic Wildlife
	(2A)	(2B)	(3A)	(3C)	(3C)	(3D)
Pollution Indicators (mg/l) Total Suspended Solids	-	90	35	-	-	-
Phosphate(mg P/l)	0.05	0.05	-	-	-	-

The concentration of Phosphate is found to have exceeded the target endpoint of 0.05mg/l on several occasions in several locations as shown in Table 13. The state considers sites where more than 25 percent of the samples exceed as non-supporting. Since phosphorus is adsorbed to sediment particles, the control of sediment production is important to reduce phosphorus.

Table 13 Percent of historic water quality samples which exceeded water quality

indicator concentrations from 1976 to 1992 (shown in red):

LOCATION	DATES	TP
LITTLE BEAR 576-above Davenport Crk 577-Davenport above S. Fork 578-below Porcupine 575-above conf. w/S. Fork 574-above conf. w/E. Fork 570-west of Avon 567-below White Trout farm 565-below Hyrum reservoir 559-below Wellsville 550-above Logan River	1990-92 1990-92 1976-79 1990-92 1990-92 1977-92 1977-92 1976-92 1992 1977-92	8 8 18 0 17 31 80 61 88 66

Sources of Water Quality Impairments

• Unstable stream banks contribute sediments
• Stream channel erosion
• Erosion of range-land due to reduced vegetative cover caused by overgrazing from livestock and wildlife
• Nutrients carried by runoff from the cropland
• Wellsville sewage treatment lagoons contributing to TP loads
• Hyrum reservoir as a substantial source of dissolved total phosphorus

Remedial Measures

• Installation of waste management systems in critical treatment areas
• Irrigation water management to reduce nutrient input from cropland
• Reduce animal waste runoff by implementing conservation nutrient management
• Restore stability of stream banks
• Vegetation plantings
• Restrict channel access to livestock
• Provide watering facilities for livestock

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Data Sources

1. Digital Elevation Model (DEM) : http://seamless.usgs.gov/

2. Landwehr, Lumb, and Slack “Hydro-Climate Data Network (HCDN): Streamflow Data Set, 1874-1988.” USGS Water-Resources Investigations Report 93-4076. http://water.usgs.gov/pubs/wri/wri934076/

3. Little Bear – Logan Watershed boundary : http://water.usgs.gov/lookup/getspatial?huc250k

4. Little Bear River Watershed TMDL, Utah Department of Environmental Quality (http://www.eq.state.ut.us)

5. Precipitation data and location of weather stations : http://www.wrcc.dri.edu/summary/climsmut.html

6. River Reach Files : http://water.usgs.gov/lookup/getspatial?erf1

7. U.S. Environmental Protection Agency Little Bear-Logan Watershed Profile http://cfpub.epa.gov/surf/huc.cfm?huc_code=16010203

8. U.S. Geological Survey, Real-Time Data for Utah: Streamflow http://waterdata.usgs.gov/ut/nwis/rt/

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