introduction to gis - final research report

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EVS 570Introduction to Geographic Information Systems Taylor Thompson

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EVS 570: INTRODUCTION TO GEOGRAPHIC INFORMATION SYSTEMSSubmitted to Mr. James Ault

Exploring Land Utilization and Water Quality

in the Cedar Creek Watershed

Spring 2014

Taylor Thompson

Environmental Science Department

Creighton University


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Contents

Introduction4

Background.4

Methodology.7

Results and Conclusions..12

References20


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List of Tables

Table 1: Land Use Categories and Codes

Table 2: Water Quality Standards Scales

List of Maps

Map 1:Agricultural and Quarry Land Use Types Surrounding Cedar Creek Water Quality

Monitoring Station with - Orthrophosphorus Levels12

Map 2:Agricultural and Urban Residential Use Types Surrounding Lake Olathe Water

Quality Monitoring Station with Low Dissolved Oxygen Levels13

Map 3: Urban Residential and Agriculture Land Use Types Surrounding Lake Olathe WaterQuality Monitoring Station with High Total Chlorophyll15

Map 4: Urban Residential, Agriculture, and Quarry Land Use Types Surrounding Lake

Olathe Water Quality Monitoring Station with High Nitrate + Nitrite17


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Introduction

Currently, more than half of the Cedar Creek Watershed in Johnson County, Kansas is

cropland (54%) and agricultural runoff is the greatest source of nutrient inputs into the

watershed. The City of Olathe estimates that the total annual loads of phosphorus and

nitrogen will reach 9,630 pounds and 639,000 pounds respectively within the next 25 to 30

years. The City of Olathe is planning to fully urbanize the watershed area during this time.

After fully developed, the watershed will have 0% cropland and grassland. The urban

residential and commercial areas will increase from the current 15% to 62%. Because of

this, urban runoff will become the major runoff source of nutrients in the watershed.

Fertilizers and excess nutrients coming from storm water runoff from urban yards, streets,

or crop fields negatively affect water sources. This fact instills an importance to know how

this urban runoff will affect the health of the bodies of water within the watershed.

Therefore, the Cedar Creek Watershed in northeast Kansas was analyzed. This watershed

holds Lake Olathe, Cedar Lake, and Cedar Creek. Cedar Lake flows into Lake Olathe through

Cedar Creek, and in many ways, Cedar Creek serves as a buffer from environmental harm

for Lake Olathe. My question was: Is there a distinct correlation between high levels of

phosphorus, nitrogen, and chlorophyll-a levels and low levels of dissolved oxygen in the lake

and population density surrounding the lake, broken down by the type of development?

Background

Eutrophication is the process by which a body of water acquires a high concentration of

nutrients, especially phosphates and nitrates. These typically promote excessive growth of

algae. As the algae die and decompose, high levels of organic matter and the decomposing

organisms deplete the water of available oxygen, causing the death of other organisms,

such as fish. Eutrophication is a natural, slow-aging process for a water body, but human

activity greatly speeds up the process. This process is taking place in the Cedar Creek

Watershed and day-by-day measurements must be taken in order to track the effects of this

sprawl on these precious water sources.

Under natural conditions, phosphorus levels are typically low in aquatic environments,

but human activities have resulted in excessive phosphorus loading into many freshwater


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systems. Total phosphorus concentrations in several water samples collected from Cedar

Creek and Lake Olathe during storm runoff and non-runoff visits in 2000 exceeded the

recommended guideline of 0.10 milligrams per liter, which has been established by the

USEPA to avoid algal blooms (U.S. Environmental Protection Agency, 1986). Total

phosphorus in water samples from Cedar Creek and Lake Olathe can originate from

agricultural, industrial, or residential activities in the watershed or from the natural

background sources. Phosphorus also may be attributed, in part, to internal loading, which

is the release of phosphorus into the water column from the lake bottom sediment that

originated from the previously mentioned sources. Orthophosphorus is dissolved inorganic

phosphate, or the portion of the total phosphorus, and is the form that is required by plants

for growth. This is of particular concern for lakes and streams because orthophosphates are

immediately available in the water for algal uptake. It is a soluble form of phosphorus that is

readily available to algae and under certain conditions can stimulate excess algae growth to

subsequent depletion of dissolved oxygen. Natural processes induced orthophosphates, but

major human-influenced sources include partially treated and untreated sewage, runoff

from urban and agricultural land, and some fertilizers. The concentrations of

orthophosphates can vary greatly over short periods of time because plants can quickly take

it up and then release it. The level established by the EPA is 0.10 milligrams per liter.In addition to bacteria sampling, water from Cedar Creek and Lake Olathe has been

sampled for chlorophyll-a, which is present in most algae and is used a measurement of

algal biomass and production and as an indication of potential eutrophication. Lakes and

streams with concentrations of chlorophyll-a greater than 12 to 20 ug/L are considered

eutrophic, or nutrient-enriched, by the Kansas Department of Health and Environment

(Kansas Department of Environment 1998 in Mau 2000). Water samples from Cedar Creek

in 2000 for chlorophyll-a frequently exceeded 12 to 20 ug/L and chlorophyll-aconcentrations in all water samples collected from Lake Olathe equaled or exceeded 12 to

20 ug/L during 2000 and 2001. The effects of eutrophication are numerous, included loss of

habitat for aquatic species, decreases in biodiversity, decreases in desirability as a water


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supply and recreational sources, and lost economic value and revenues from decreased

water-supply use and recreational activities (Mau 2000).

Dissolved-oxygen concentrations are also important to measure as less than 1.0

milligram per liter concentrations can indicate the increased possibility of elevated

manganese concentrations (Rasmussen and McAllister 2005). Manganese can cause

treatment problems in water treatment plants. Normally, manganese is held in the bottom

sediments as an insoluble particulate, but during warm summer months, the dissolved

oxygen content in the water may decrease near this bottom sediment. A lack of rainfall

with inadequate mixing of fresh and stagnant water, increased algae growth, deterioration

of organic matter as the water warms up, and low wind conditions, can all contribute to

depletion of dissolved oxygen levels. If a reservoir becomes stratified as a function of

temperature, the bottom layer will be very low in dissolved oxygen (Can Drinking Water

Reservoirs Develop Manganese Problems Due to Temperature Stratification?). This can lead

to anaerobic conditions in the deep waters of the lake. Manganese is then converted from

its insoluble oxide form to soluble ions that are can leach out of the bottom sediment,

which can lead to poor drinking water and color and staining problems.

The presence of nitrogen is essential for plant growth, as well. It is used to synthesize

proteins and it constitutes the major part of living substances. It is very mobile and thecontribution of it to water bodies can lead to excessive algal growth, which may in turn

produce taste-and-odor problems, stress organisms, and decrease the aesthetic and

recreational value of the water body. There are many potential sources of nitrogen in the

Lake Olathe watershed including leachate from septic systems, runoff from livestock

wastes, runoff from agricultural and residential application of synthetic fertilizers, and

atmospheric deposition (Adams in Wetzel 2001).The application of fertilizers in Kansas

had increased 10-fold in the past 40 years (Kansas Department of Health and Environment1996). This nitrogen is then washed off into streams or can infiltrate into the groundwater.

Atmospheric deposition is another source as the atmosphere is 78% nitrogen. Many

drinking water contaminants, like nitrate and nitrite, are naturally occurring, but excessive


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amounts can cause blue-baby syndrome and other issues. The maximum level is set at 1

milligram per liter of nitrate + nitrite (Data Management And Compliance Unit).

Methodology

To determine the environmental health of the Cedar Creek Watershed, I gathered data

on the development surrounding the lake and the population density according to each

type of land use. It was helpful to know the population density surrounding the bodies of

water, as higher populations may have a greater impact on bodies of water. I examined how

the development surrounding the lake has affected the phosphorus and nitrogen levels in

the lake, which in turn can deplete the lake of oxygen, creating an environmental unhealthy

lake.

Land Use Data

To do this, I gathered shapefiles, layers, attribute tables, etc. that work with the ArcMap

to map out this area and to see the possible correlation between highly eutrophic and

polluted areas of the lake and the developed areas. My question was: Is there a distinct

correlation between high levels of phosphorus, nitrogen, and chlorophyll-a levels and low

levels of dissolved oxygen in the lake and population density surrounding the lake, broken

down by the type of development?

To understand the make-up of the development surrounding the lake, I had to look at

map layers of the area surrounding the lake of whether the area is residential, commercial,

park space, or undeveloped. Once I had data gathered, I found that it would be more

beneficial to split up the layers into the actual land use as documented by the Johnson

County AIMS Department. In the end, my land use layers were split into quarries, parks,

urban residential, rural residential, industrial, agricultural, and commercial. Parks, urban

residential, industrial, agriculture, and commercial were further broken down into more

specific land uses to find a more accurate cause of pollution if necessary. Clearly,

undeveloped land would have less of an impact on the health of the lake as opposed to

commercial, residential, industrial, agricultural, or park space. To understand the health of

the lake in response to these areas, I had to find a data that showed the levels of


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phosphorus, nitrogen, total chlorophyll, and dissolved oxygen at several points in

watershed.

Table 1: Land Use Categories and Codes

CATEGORY CODE

Agriculture 800, 812, 811V, 740

Commercial 431A, 551, 460, 639, 638, 215, 611, 584, 725,

644, 6441, 323, 670, 670H, 6701, 516, 1166,

541, 5411, 537, 5371, 655, 661, 531, 6631, 583,

5831, 654, 739, 728, 729, 651, 665, 657, 171, 664,

635, 6351, 656, 243A, 515, 271, 522, 631, 649,

699, 458P, 458, 542, 581, 532, 5321, 642, 708, 633,

533, 100S, 539, 815, 100U, 500, 700, 650, 6501,

636, 514, 5141, 512, 5121, 513, 5131, 511, 511A,

5111

Rural Residential 811Urban Residential 115, 116, 645, 645H, 659, 112, 114, 683, 119,

1192, 631H, 634, 6341, 199, 199C, 199X, 100P,

124, 111, 111V, 113, 100, 100C, 100D, 100F, 100X,

100T, 120

Parks 735, 7351, 932, 736

Quarries 915

Industrial 326, 481, 3411, 322, 281, 340, 282, 411, 500R,916, 484, 485, 4851, 333, 3331, 517, 200, 200A,

483, 4831

Source: Johnson County AIMS Department

My process included identifying my variables, which were the Lake Olathe, Cedar Lake,

and Cedar Creek shapefiles, the Cedar Creek Watershed shapefile, land use designations,

population densities, the location of different water quality monitoring stations within the

watershed, and data on the phosphorus, nitrogen, total chlorophyll, and dissolved oxygen

levels for a certain year. I then downloaded the world topography basemap from the online

GIS system and zoomed in to the watershed area and created a bookmark to easily access

this location again. I then worked on gathering data for each of my variables, which will be

outlined in the next paragraph.

Water Quality Data

My data was gathered from a few different sources. First, I contacted the Johnson

County AIMS Department in order to, hopefully, gain access to their shapefiles and attribute

tables for population density, the shape of the watershed, environmental data compiled


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from the Kansas Department of Health and Environment, and zoning to map out various

land uses within the watershed. From their free data link on their website I was able to

download a shapefile that highlighted the major streets in the watershed and the streams.

They quickly sent me files that included all of my requested data. The GIS Analyst kindly

buffered the files to just the Cedar Creek Watershed, as well, which saved me some time.

To gather the water quality readings that I needed, I went to the United States Geological

Surveys website and found their data charts for Kansas real-time water quality. I found that

there were three water quality monitoring stations within the watershed (06892450 Olathe

Lake near Olathe, KS, 06892495 Cedar Creek near DeSoto, KS, and 06892440 Cedar Creek at

Highway 56 at Olathe, KS). Unfortunately, I wanted to compare the data within one year,

but 2004 was the last year they were all still taking water samples due to a lack of funding.

That has been the most limiting part of my project, as my water quality samples are not

current. I also found that each station did not measure the exact same water qualities. All

three of the sites measured average dissolved oxygen, but the station in Cedar Creek near

DeSoto, KS did not measure the computed nitrate + nitrite, computed dissolved

orthophosphorus, or the total chlorophyll. Therefore, the 0 readings symbolize that no

data was available.

Table 2: Water Quality StandardsTotal Chlorophyll

(ug/L)

Orthophosphorus

(mg/L-P)

Nitrate + Nitrite

(mg/L-N)

Dissolved Oxygen

(mg/L)

03.99 0 - .024 0 - .24 12.9910

47.99 .025 - .049 .25 - .49 9.997

811.99 .050 - .074 .50 - .74 6.994

12+ .075 - .10 .75 - 1 3.991

Source: USGS Kansas Real-Time Water Quality

Process

I used the United States Geological Surveys data and created my own attribute tables

that recorded daily readings of each water quality standard for 2004. I then averaged each

quarter of each standard to find the average water quality for each standard for each three


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month period. From the averages, I created a new attribute table with the following column

headers: quarter, location, latitude, longitude, average dissolved oxygen (mg/L), average

computer nitrate + nitrite (mg/L-N), average computed dissolved orthophosphorus (mg/L-P)

and average total chlorophyll (ug/L). I then had to find the correct latitude and longitude for

each of the three water quality monitoring stations. I did this by contacting the USGS Kansas

Water Science Center. Teresa Rasmussen provided me with the proper latitude and

longitude for each of the three stations. I had great trouble using those to display the XY

data on my basemap though. After a long process speaking of Mr. Ault emailing the Esri

support staff, I was provided with the proper steps to add two new fields to my attribute

tables (DDLat and DDLong). To calculate the decimal degrees of latitude and longitude for

each of the two new fields, I used the Excel formula "=LEFT(E2,2)+(RIGHT(E2,7)/60)" for

the Latitude (where E2 is the cell with the DMS Latitude); and "=-

1*(LEFT(G2,2)+(RIGHT(G2,7)/60))" for the Longitude (where G2 is the cell for the DMS

Longitude) and set the columns to Numeric. I then added the updated attribute table to

my geodatabase by importing it as a table, but I had to edit the geographic coordinate

system to WGS1984 in order to have my station points display correctly.

To my basemap, I added the zoning shapefile to my basemap by importing it to my

geodatabase. I then went through the entire zoning attribute table and made a list of whichzoning codes were related to each type of land use that I designated. I had to clean up and

organize the main land use attribute table that I received from the AIMS Department. The

final attribute table had the following fields: ObjectID, Shape, AreaCAcre, GeoPF,

GeoPFDesc, SALine1, LandUse, LandUseDsc, LBCSActvty, LBCSActDsc, LBCSFunctn,

LBCSFunDsc, LBCSOwnShp, LBCSStruct,LBCSStrDsc, LBCSSite, LBCSSitDsc, DwellUnits,

YearBuilt, Zoning, Shape_Length, and Shape_Area. From that list, I then used the select by

attribute tool in order to create a new selection for each type of land use. Then, I right-clicked on each layer and created a new layer file, saved it to my file shapefiles, and then

imported it into my geodatabase. Within each of my new land use layers I then edited the

layers properties by going to the symbology tab, clicking on categories, and then unique

values to separate out the specific land uses within each larger land use. By clicking add all


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values and choosing LandUse as the Value Field within the symbology tab I was able to

do this. I then chose a color gradient so each land use parcel would be displayed as a

different color. I completed this process for each larger land use area.

To properly display population density differences I added the supplied attribute table

to my geodatabase by importing it as a feature class. I edited its layer properties under the

symbology tab. Under quantities, I decided to display the density differences through a

color gradient, with the darker color being more population dense. As the value I chose the

field Pop100 and normalization Shape_Area in order to divide the population of each

parcel of land by its area in order to determine the density. I then chose a color ramp and

kept five classes of densities. I saved the result as a layer and imported it as a feature class

into my geodatabase.

To display the water quality standards in a visually appealing way I used the select by

attribute tool to select each type of water quality measurement type to create four

different selections. After I selected each one, I right-clicked the main environmental data

layer that I imported from my created attribute table and held my mouse over Selection

and then clicked Create Layer from Selected Features. After completing this for each

water quality measurement type, I used the select by attribute tool again to create eight

new layers; four of them were separated out by quarter and the other four were separatedout by the water quality measurement type. In this way, I was able to maintain four layers

based on water quality measurement type to show all of the measurements in one layer,

but also was able to display the measurements through group layers based on the type of

water quality measurement and the specific quarter. I further separated the four water

quality measurement type layers and quarter layers by right-clicking on all of them, opening

up their properties box, and changing their symbology by going to Categories, Unique

Values, and then changing the Value Field to each different water quality measurementtype. I then clicked on Add All Values and changed each resulting values symbol to a

circle colored green, blue, yellow, or red, depending on the scale for that specific water

quality measurement type.


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Results and Conclusions

There is not enough evidence to point to a specific causation, possibly only a slight

correlation between land use and water quality standards in the Cedar Creek Watershed. All

of the orthophosphorus readings were in the safest range, 0 - .024, but it is worth

mentioning that levels of orthophosphorus must still be recorded because concentrations

can vary widely over short periods of time as plants take it up and release it. The station by

Cedar Creek near Highway 56 displayed the highest levels of orthophosphorus, but they

were still in the safe range. A possible explanation as to why this station had the highest

levels is not population density (therefore residential activity) because it is in the lowest

population density range, but more likely agriculture and quarries because of their close

proximity to this stream. Runoff from agricultural sites and draining toxic wastes from

quarries may have something to do with these higher levels of orthophosphorus.

Map 1: Agricultural and Quarry Land Use Types Surrounding Cedar Creek Water Quality

Monitoring Station - Orthrophosphorus Levels

Quarter 4

Average Computed Orthophosphorus (mg/L-P)

Agriculture


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Average dissolved oxygen levels were the next least worrisome issue that was facing the

Cedar Creek Watershed. None of the readings at each of the three water sources fell into

the highest level of concern. Only quarter three (July, August, September) featured one

relatively low reading of dissolved oxygen. The rest of the readings fell into the ranges of

12.9910 and 9.997. The worst reading in quarter three fell into the 6.994 range, with

a reading of an average of 6.54. This reading was taken at the Lake Olathe water quality

monitoring station in quarter three. Urban residential and agricultural activities most likely

play the largest role in this issue. Within agriculture, farming activities such as farming,

plowing, tilling, and harvesting have nearest spatial proximity to this water quality station.

Within urban residential, single family residential household activities was the specific use

within the broader category. This lower dissolved oxygen concentration indicating higher

levels of manganese ions within the deeper levels of the lake may be caused by increased

algal blooms, which are caused by increased levels of phosphorous and nitrogen from

residential fertilizer runoff. This displays only a weak correlation, though.

Map 2: Agricultural and Urban Residential Use Types Surrounding Lake Olathe Water

Quality Monitoring Station with Low Dissolved Oxygen Levels

Quarries

Quarter 3Average Dissolved Oxygen (mg/L)

Agriculture


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Total chlorophyll measurements were the next least worrisome issue that was facing

the Cedar Creek Watershed. Only one of the readings at end of the three water sources fell

into the highest level of concern, which happened in quarter one (January, February,March) at the Lake Olathe water quality monitoring site. Quarter two and three features

one relatively high reading of total chlorophyll, 10.64 (Lake Olathe) and 10.73 (Lake Olathe),

respectively. The rest of the readings were not at high levels of concern. When comparing

land use type to the highest levels of total chlorophyll measurements, a spatial correlation

Urban Residential


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may possibly be found between urban residential and agricultural areas that directly

surround the lake.

Map 3: Urban Residential and Agriculture Land Use Types Surrounding Lake Olathe Water

Quality Monitoring Station with High Total Chlorophyll

Quarter 1Total Chlorophyll (ug/L)

Agriculture


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Urban residential and agricultural activities most likely play the largest role in this issue.

Within agriculture, farming activities such as farming, plowing, tilling, and harvesting have

nearest spatial proximity to this water quality station. Within urban residential, single family

residential household activities was the specific use within the broader category. This high

level of total chlorophyll may be caused by increased algal blooms, which are caused by

increased levels of phosphorus and nitrogen fertilizers from urban and agricultural runoff.

Causation can be not be determined.Average computed nitrate + nitrite levels in the watershed displayed the highest levels

of concern on five out of the 12 readings. Quarter one featured a high level of nitrate +

nitrite at two of the three water quality monitoring stations, Lake Olathe and Cedar Creek

near Highway 56. Quarter two, three, and four featured high levels of nitrate + nitrite, but

Urban Residential


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these were only at the station in Cedar Creek near Highway 56. When comparing land use

type to the highest levels of computer nitrate + nitrite measurements, a spatial correlation

may possibly be found between urban residential, agricultural, and quarry zones that

directly surround the lake.

Map 4: Urban Residential, Agriculture, and Quarry Land Use Types Surrounding Lake Olathe

Water Quality Monitoring Station with High Computed Nitrate + Nitrite

Quarter 1Average Computed Nitrate + Nitrite (mg/L-N)

Agriculture


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To strengthen this project, current water quality samples are key, as well as a more

comprehensive study of the water quality measurements over several years. Instead of

looking at a quarterly resolution, a daily or hourly resolution would be more

comprehensive. This would provide more justification towards causation, instead of a weakcorrelation. Sediment dumping levels and flow rates would also be interesting to look at to

further understand the connection between the three bodies of water. As Cedar Lake is

connected to Lake Olathe by Cedar Creek, it is important to look at how much Cedar Lake

holds back from Lake Olathe.

Urban Residential

Quarries


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While the water quality samples were outdated by 10 years, it is clear that this cannot

be an accurate determination of the actual water quality within the Cedar Creek watershed.

Instead, it can be used as a model for future water quality samples to be integrated into a

similar type of study. The potential problems that are noted in this study can only logically

be expected to worsen due to continue land use change into uses that add more nutrients,

fertilizers, pollutants, etc. to the water sources. The City of Olathe does not use Lake Olathe

as a drinking water source anymore either, therefore even less incentive still survives to

keep the lake healthy. Recreational use of the lake has dramatically decreased, as well,

especially because the swimming beach is not open anymore. Water quality must continue

to be monitored though as land use changes, ecological changes will worsen unless proper

management techniques are put in place.


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