In partnership with the A.S. Outdoor Center and the
Huxley Spatial Institute
Hydrologic Analysis of
Lakewood
A study of WWU’s Lake Whatcom Property
Brian P. Anderson
‘14
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Table of Contents
Introduction ................................................................................................................................. 1
Literature Review ......................................................................................................................... 2
Methods ...................................................................................................................................... 4
Data ........................................................................................................................................ 4
Analysis................................................................................................................................... 5
Results ........................................................................................................................................ 6
Discussion ................................................................................................................................. 8
Works Cited ............................................................................................................................... 9
Figure 1 - Model of analysis ....................................................................................................... 6
Figure 2 - Topographic map of Lakewood property .................................................................... 7
Figure 3 - Stream flows through Lakewood ................................................................................ 7
Figure 4 - Tree survey results .................................................................................................... 8
Introduction
In the world of Geographical Information Systems/Sciences (GIS), there are countless studies
occurring to test the uses of GIS’s in various areas, such as in archeology, erosion and hydrology
modeling. In the field of archeology, GIS is being used to reconstruct prehistoric lakes, manage
and display Native American artifact discoveries both past and present, and discovering patterns
within 16 century-with gauges old cemeteries. In hydrology modeling, progress is being made in
the accuracy of modeling water flows, determining watersheds and catchments. This research
leads to progress in erosion modeling. The following paragraphs outline some of these
hydrologic and erosion modeling studies. All of this will be used to accomplish several goals.
The first will be to conduct a hydrologic analysis of Western Washington University’s Lake
Whatcom property, Lakewood. The second will be to create a topographic map of the area for
use by visitors. Finally, a tree survey will be conducted, finding trees larger than six feet in
diameter and ten feet tall.
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Literature Review
The purpose of GIS and Hydrologic Modeling – an Assessment of Progress was to measure the
progress within the author’s study area, four years after the initial study. This then leads into the
main bulk of the study; developing models to use on two types of areas. The first is a model that
uses time averaging to determine flow. This model is used to determine stream flow at ungauged
locations, which is particularly useful to my study as there are no gauges anywhere in my study
area. This assessment also includes a non-point source pollution assessment. The second is a
model that accounts for time changing the hydrologic system in question. This section includes
all water sources; atmospheric, soil, groundwater and surface water collections. It also includes a
section about the utilization of water. This second model is to be used on streams with gauges.
The authors found that their models were able to accurately track and predict stream flows and
pollution based on historical trends. This particular study is useful to me because the author
outlines how to create hydrologic models for areas that do not have any volume monitoring
stations. I plan on implementing some of these techniques in my study. This study also provides
another model in which to base my work on, aiding in the problem-solving process when my
analysis is conducted. (Maidment, 1996)
The study conducted in Assessing Watershed-Scale, Long-Term Hydrologic Impacts of Land-Use
Change Using a GIS-NPS Model examines the impacts of hydrologic nonpoint source pollution
based on land-uses, specifically what effects changes of land-use has on water pollution. The
authors created a model which assesses long-term hydrologic impacts of pollution and paired it
to a GIS to assess annual average runoff and pollution of their study area. The authors found an
increase in pollution based on the land-use change. This study is useful to mine because it deals
with nonpoint pollution sources. Though my study does not cover the scope of pollution, the
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models used in this study can be applied to aid in determining amounts of soil erosion based on
water flow through an area. (Bhaduri, Harbor, Engel, & Grove, 2000)
This study in Review of GIS Applications in Hydrologic Modeling reviews the past efforts and
current trends in using Digital Elevation Models (DEMs) and GIS to perform hydrologic analysis
of areas. The authors discuss different presentation methods to best convey the hydrologic
processes to your audience, based on past studies. The authors also analyze the best methods to
perform a hydrologic analysis, based on the studies presented in the article. They also present a
method for erosion prediction and control. Rather than requiring runoff information, this method
requires soil, land cover, rainfall and topographic properties. This study is useful to me because it
gives me references in which to base my erosion prediction models. (DeVantier & Feldman,
1993)
In their study, the authors of Comparison of the performance of flow-routing algorithms used in
GIS-based hydrologic analysis calculated flow direction and water catchments for their study
area. The authors studied the effects of terrain shape on water and sediment movement across a
landscape, using several different algorithms to compare one to another. They also addressed
problems such as the acceleration of soil erosion and nonpoint pollution. The authors concluded
that all around, their models produced poor results; however one algorithm stood apart and
proved important for calculating sediment transport capacity. After review, this algorithm is
similar to the algorithm reviewed in the above article and will provide useful in setting up a
model for erosion prediction in my study area. (Wilson, Lam, & Deng, 2007)
The authors of the study in FloodwayGIS: An ArcGIS Visualization Environment to Remodel a
Floodway aimed to create a model for floodway boundaries for use with FEMA and local
governments. The model the authors created is to be used with a commercial GIS, ArcGIS in
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their case, to produce a mapping algorithm based on Triangulated Irregular Network (TIN)
intersections to produce the desired boundaries. These boundaries are then mapped in the Digital
Floor Insurance Rate Maps to determine flood insurance rates. The authors found their model
better predicted the floodway boundaries than the current models used by FEMA. This study
may seem specialized and irrelevant to my study; however, the methods used in this study create
a basis for my own study. Their study provides methods for determining locations of waterways
and the ability to predict water flow during and after storms. The increase in water flow will also
increase erosion, highlighting areas in which preventative erosion methods should be employed.
(Selvanathan & Dymond, 2010)
All of these studies have one thing in common: they cover large areas. My research will be
confined to a relatively small area, which will pose its own problem. Hydrologic modeling is
normally done on a large scale because, in hydrology, the larger area must be considered instead
of the small, specific areas. To counter this, I will perform an analysis on the entire area, and
then cut down my results to the study area. To further my research, I will continue to research
similar studies involving hydrologic and erosion modeling. As of yet, I haven’t found any studies
that encompass both models; rather the studies focus on either hydrologic or erosion modeling.
Methods
Data
The data used in this study will come from a wide variety of sources, including data I created
myself. I obtained land parcel records from the Whatcom County GIS department, which
unfortunately proved to be somewhat inaccurate and manual editing of the property lines of the
Lakewood site was needed. From Whatcom Transportation Authority (WTA) I received point
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and line data that show bus routes and stops, two of which are at the Lakewood property. These
data were received as text files in American Standard Code for Information Interchange (ASCII)
coding and needed to be converted into vector format. From the City of Bellingham GIS website,
I obtained elevation contour lines, street locations, and classification and use data. After I had
edited my data received from Whatcom County GIS, I received parcel polygon data from the
City of Bellingham GIS which I used to ensure I had edited my property lines correctly. The
final source of data I received from an outside agency was Light Detection And Ranging
(LiDAR) data from the Puget Sound LiDAR Consortium (PSLC), who received the data from
the City of Bellingham and Whatcom County GIS. The PSLC acts as a LiDAR clearing house
for most all data surrounding the Puget Sound. This LiDAR data will be used to create a digital
elevation model (DEM) of Lakewood and the surrounding land. As part of my study I will also
be collecting point data of trees meeting the specific criteria I will outline. All of my data, except
for the LiDAR data which is raster, is in vector format. All data was projected or re-projected
into the NAD1983 State Plane Washington North (US Feet) projection.
Analysis
For my study, I conducted a hydrologic analysis of the area surrounding and including
Lakewood. I analyzed the surrounding area as well because the Lakewood parcel is too small of
an area to perform a standalone analysis. The starting point of my analysis was to resample the
DEM from three meter cells to ten meter cells. This was performed because the original data was
too accurate and was not able to be successfully processed due to the large file size. Next I
needed to fill in any holes in the elevation data using a “Fill” function. Then the flow direction
was determined, based on the slope of each cell in my DEM. This particular piece of data was
then used to complete eight other processes, including determining the lengths of streams and
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Orders, creating a basin boundary, watersheds and catchments, accumulation rates (flow rates)
and direction of water flow. To define my streams, I set a threshold of 1000 cells draining into
one cell. At the end of my analysis, I produced several products, including a topographic map
showing the location of streams flowing through Lakewood, with metadata on their Order. All of
this data will be converted to Computer Aided Design and Adobe Illustrator formats for use by
the Industrial Design students.
Figure 1 - Model of analysis
Results
My analysis concluded that there were two streams running through the property, both on the
east side of it. It was also found that they were small, both second order. My tree survey found
that there are 19 trees that meet my requirements for expanding the High Ropes Challenge
Course. It should be noted that trees currently being used on the course were excluded from this
survey.
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Figure 2 - Topographic map of Lakewood property
Figure 3 - Stream flows through Lakewood
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Figure 4 - Tree survey results
Discussion
This study was very relevant to the everyday operations of the Lakewood site. As of now, there
is an interactive web map, electronic and paper topographic maps and data on tree locations to be
used in the future for expanding the high ropes course. As a whole, the study failed. The analysis
failed to identify the one stream that does run through Lakewood; rather, the analysis identified
two streams that do not exist on the property. If one were to examine the Hillshade produced
from the DEM, one would clearly identify the real stream on the west side of the property. I feel
this error was created as a result of resampling the DEM to larger cell sizes. Had I resampled the
cells to five meters instead of ten, I believe the analysis would have correctly identified the
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streams. The steps I took in my analysis were valid, and worked; the errors that formed were a
direct result of taking overly accurate data thus making it less accurate. However, when I
changed the cell drainage threshold from 1000 to 250, the true stream did begin to form. The
reason I didn’t permanently change the threshold was due to the many other ‘streams’ the
analysis began to identify. A different approach to solving the data issue I had would be to use a
computer with stronger processors. The reason I resampled to larger cells in the first place was
that there was more data than the computers I used were able to handle. With the level of
computer knowledge I have, I can also infer that there was a software problem; ArcGIS can only
handle a data set so large and I believe I breached that threshold. In the future, with better
software and hardware, analysis of Lakewood at three meter cell sizes is possible. In spite of the
limitations above, this methodology of analysis succeeded and is valid for use in future studies.
Works Cited
Bhaduri, B., Harbor, J., Engel, B., & Grove, M. (2000). Assessing Watershed-Scale, Long-Term
hydrologic Impacts of lane-Use Change Using a GIS-NPS Model. Environmental
Management, 643-658.
DeVantier, B. A., & Feldman, A. D. (1993). Review of GIS Applications in Hydrologic modeling.
Hydrologic Engineering, 3-16.
Flower, A. (2014, Feburary 21). Lab 6: Hydrology and Watershed Analysis. Retrieved from
ENVS421: GIS Databases:
https://wwu.instructure.com/courses/858924/assignments/2358190
Flower, A. (2014, Feburary 28). Lab 7: Network Analysis. Retrieved from ENVS421; GIS
Databases: https://wwu.instructure.com/courses/858924/assignments/2358191
Maidment, D. R. (1996, January 24). GIS and Hydrologic Modeling - an Assessment of
Progress. Retrieved from University of Texax:
http://www.ce.utexas.edu/prof/maidment/gishydro/meetings/santafe/santafe.htm
Mayfield, J. (2014, Janurary 24). Lakewood Presentation. Retrieved from ENVS421; GIS
Databases:
https://wwu.instructure.com/courses/858924/files/25959706?module_item_id=5219473
Selvanathan, S., & Dymond, R. L. (2010). FloodwayGIS: An ArcGIS Visualization Envirionment
to Remodel a Floodway. Transactions inGIS, 671-688.
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Wilson, J. P., Lam, C. S., & Deng, Y. (2007). Comparison of the performance of flow-routing
algorithms used in GIS-based hydrologic analysis. Hydrological Processes, 1026-1044.
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