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Regional Program Priority
Issue Areas
Regional Initiatives
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Introduction:
ArcView is an effective tool for building dynamic data maps
for any geographical region. ArcView is a Geographical Information
System (GIS), which allows for the layering of different sets
of geographical data. Each set of data is layered over the
next, so that each layer can be viewed separately or all at
once.
Every set of information that is input into ArcView is specific
for its location in the coordinate system of the database.
This allows for precise information about any features on
the map, which are user-defined. ArcView gives the user full
control to customize the map to their specific needs.
One hot topic is the building of maps for municipal stormwater
management plans. With ArcView, maps of the soils, streams,
land use, protection areas, etc., can be added to a specific
municipal boundary in the county. This overview shows how
to use ArcView to create the basic information maps for a
municipal stormwater management plan.
Building
Maps:
Many popular maps for various geographical data sets have
already been created for the state of New Jersey. These can
be found at the New
Jersey Department of Environmental Protection (NJDEP) GIS
website. There is a scroll menu which allows for the selection
of a specific digital layer under the GIS Data Downloads.
The map may be downloaded by selecting the options you desire
and then clicking on the download button. Then extract the
(.zip) file into a folder that you have created to store your
data. The file that you wish to view is labeled as a shapefile,
or (.shp). A shapefile stores the geometry and information
about the feature. To open the shapefile for viewing, start
a new project. In the view menu on the top toolbar, add a
new theme to the project. ArcView can import feature data
sources or image data sources according to the file type.
A shapefile is a feature data source so select accordingly.
Once the shapefile is selected its name will appear on the
toolbar on the left side of the screen. This is the viewing
toolbar. To view or hide the theme, check the box on or off.
When the box is checked, the view will appear. When more than
one theme is loaded into the view area, the layer which is
on top in the viewing toolbar will be in front. This can be
changed accordingly.
To view information about a particular location in one theme,
that theme must be highlighted in the viewing toolbar. Then
the information button may be selected and placed on a specific
location. Click once and an information box will appear. One
important concept in ArcView to remember is that the information
about a certain layer can only be viewed if that theme is
selected. We will now look at the recommended maps for building
a stormwater municipal management plan.
Recommended Maps for Municipal
Stormwater Management Plans:
Municipal
Boundaries
The first layer for a stormwater plan will be the municipal
boundaries. A local county or statewide map may be selected
from the NJDEP GIS
website. The boundaries allows for the clipping of streams,
soils, land use, and other features which lie outside of the
boundary. It is also useful to see the geometry of the municipality
in relation to the other features of the location. A specific
boundary may be clipped from the rest of the surrounding boundaries
by using the geowizard processing extension in ArcView. This
allows for the selection of one or more boundaries to be in
view. By double clicking on the boundary layer on the viewing
toolbar, the boundary may be changed into an outline for better
viewing.
return to recommended
maps
Streams
The streams layer may also be downloaded from the NJDEP
GIS website. The streams layer may be downloaded for every
county in New Jersey. Once the streams layer is downloaded
it may be clipped to fit the municipal boundary. The streams
may also be sorted so the thickness of the line correlates
to the depth of the stream. This may be performed by changing
the legend type to sort by graduating symbol and then changing
the classification field to order. Each stream, tributary,
creek, or brook may be labeled by using the label button on
the top toolbar. To label a particular body of water, click
on the label button and then click on that body of water.
The name will appear, and by double-clicking on the name,
a text box will appear. Here the name and the angle of the
box may be edited.
return to recommended
maps
Land
Use
The land use layer may be downloaded from the NJDEP
GIS website. Here, land use data may be selected from
either 1986 or 1995/1997. Once the selection occurs, the next
step is to choose which watershed management group the municipal
boundary is in. Then, the map may be downloaded into ArcView
for viewing. Again, land use may be clipped to the municipal
boundaries and custom sorted by changing the legend type.
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to recommended maps
Aerial Photographs
One exceptional feature of ArcView is its ability to display
image data sources with feature data sources. This allows
for the viewing of real land images and data layers at the
same time. Importing an image is the same as importing a shapefile
into the view. By going to the view menu on the top toolbar
and selecting add a theme, the image may be selected by changing
the data source type option to image data source. This data
layer may be downloaded from the i-MapNJ
1995 Aerial Photography site.
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to recommended maps
USGS Quadrangles
The Quad maps are topographical maps of the selected region.
These may be downloaded from the Rutgers
Geography Topographic Map Download Depot. To select the
maps to use, you must first convert your municipal boundary
into a meter scale. The topographical maps are designed in
meters, and the municipal boundary maps are in feet. To covert
the boundary, you must use the Projection Utility Wizard extension
in ArcView. After you select this wizard, you will be prompted
to select a file to project. Select the appropriate file and
then click next. Then change the coordinate system type to
(projected), and then change the name to (NAD 1983_New_Jersey)
and the units to (foot). Then select the Datum tab, and change
the name to (NAD_1983_to_NAD_1927_NADCON). After you select
these attributes, click next and you will be prompted to choose
the units which you desire. Select (NAD_1927_UTM_ZONE18N)
for the name and Meter for the units. This will change the
coordinates of the municipal boundary, and you will be able
to see the boundary after you select it on the viewing toolbar.
Now you can select the quad maps to
view with the municipal boundary. These maps are image data
sources (.tif) and can be added when selected as image data
sources. However, some maps may have extra borders surrounding
the map itself and may need to be trimmed. A map edge without
a border may be selected to overlap on top of another map
with a border so that there is no spacing between each one.
This may be performed by choosing the location at which you
want the map without the border to cover the map with the
border. Determine the location at which you want to cover
the map with a border, and click on the theme properties of
the map on top. Make sure that this map is on top of the one
you want to cover. At the theme properties box, enter either
the x or y coordinate you have chosen. The map on top should
now cover over the border of the map below it.
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to recommended maps
Groundwater
Recharge Areas
The groundwater recharge area map is not listed under the
main menu of the GIS section in the NJDEP website. However,
it can be downloaded at the geodata
section of the site. There is a groundwater recharge map for
every county in New Jersey. The recharge areas are where water
moves downward from a high topographic area into a saturation
zone. This movement replenishes groundwater.
return
to recommended maps
Well
Head Protection Areas
This area depicts the horizontal reach of groundwater captured
by a well pumping station. Each protection area represents
a time frame for groundwater travel to the well over a two,
five, and twelve year period. The Well Head Protection Area
map for each county may be downloaded from the NJDEP
GIS website. However, before loading the maps into ArcView,
they must be converted into a shape file. The maps are a different
file extension (.e00), and are not image or data sources which
can be viewed by ArcView. To convert the maps into shape files,
the program Import71 is necessary. At the menu box of Import71,
browse for the map file that you need to convert at the Export
Filename field. Once you have chosen the file to export, browse
for the same file in the Output Data Source field, and delete
the extension (.e00) to the filename. Select OK and the file
will be converted to a shape file for viewing. The map will
be a feature data source.
return
to recommended maps
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