Strip Chart Basics

The strip chart is built to represent an interstate highway as a straight line leaving each interchange diagram in the middle of the top and bottom sides. As such some interchange diagrams will appear skewed from their actual appearance as shown in the linked Terraserver photo or topographic map. This also happens because of the drawing program that I use which makes it easier to draw vertical or horizontal lines of a desired configuration and color than it does to draw lines at other angles. The mainline freeway lines remain at one pixel spacing unless there is reason to make adjustments (such as median separated express lanes or left lane exits). Curves not present on actual road or ramp surfaces may appear in the interchange diagram in the interest of maintaining a standard width for the diagrams. Diagrams expand in length as needed.

Strip Chart Description

Start Vancouver, WA   (I-5) Finish Tualatin, OR   (I-5) Passes Vancouver, WA Portland Int'l Airport Clackamas, OR Oregon City, OR West Linn, OR Length 36 miles Terminates None Spurs None Meets I-84	Notes I-205 in Washington/Oregon is the Portland, OR bypass on the east side. It connects to I-5 on the north end between Vancouver, WA and Woodland, WA, and to I-5 on the south end between Tualatin, OR and Wilsonville, OR. Access I-205 provides access to the eastern and southern suburbs of the Portland metropolitan area as well as the Portland International Airport

The strip chart description holds some basic information about the described highway. On the left is a set of basic statistics about the highway including:

• Start -- the north or east end of the highway including the nearest locality and, if the end is at an interchange with another interstate, the crossing highway. This will always have a link to the top of the strip chart. For 3di's that completely loop around cities and have no ends, the link will go to the exit with the highest number.
• Finish -- the south or west end of the highway including the nearest locality and, if the end is at an interchange with another interstate, the crossing highway. This will always have a link to the bottom of the strip chart. For 3di's that completely loop around cities and have no ends, the link will go to the exit with the lowest number.
• Passes -- the major localities by which the highway passes over its entire length. Any locality that appears on the strip chart will have a link to that part of the strip chart. For the other localities, use the state links to load the appropriate strip chart.
• States -- the states that the highway passes through. If this strip chart contains exits within a state, that state's link will take you to the state's first exit in the strip chart. If this strip chart does not contain exits within a state, the state's link will load the highway's strip chart containing that state's exits.
• Length -- the total length of the highway in miles.
• Terminations -- the interstate highways that end at this highway. If the strip chart is for a 2di, this list will not include 3di's that are based from the highway (these are included in the loops/spurs section). For any listed highway termination that appears on this strip chart, a link will go to that place on the strip chart.
• Spurs/Loops -- the 3di's that base from this highway. All appear with a locality description. For those appearing on this strip chart, a link will go to that place on the strip chart. If the strip chart is for a 3di, this section will contain nothing.
• Crossings -- the interstate highways not previously listed that cross this highway. For those appearing on this strip chart, a link will go to that place on the strip chart.

In the middle is a brief text description. The 'Notes' section tells why the highway exists, a more detailed description of its end points and any details concerning the highway in the selected state(s) including express lanes, HOV lanes, any continuing lanes that separate from the mainline highway.

To the right is the highway shield.

Strip Chart Overview Map

The overview map shows the location of the highway with relation to the rest of the country. The parts of the map that you will probably be interested in will be the state lines (marked in white), the interstate highways (marked by the heavier red lines) and my additions to the map indicating the location of the selected interstate highway (maked in purple).

My additions will come in the form of either a purple line marking the location of the selected highway or a purple box around the locality of a 3di that is too short to show on the map.

For those that are interested, the other markings on the map include:

• Amtrak routes -- black dotted lines
• National Highway System routes (non-interstate) -- thinner red lines
• Major rail routes (not followed by Amtrak) -- thin black lines
• Major seaports -- small white squares
• Major airports -- small black circles
• Border crossings -- small red dots on the international borders

Strip Chart Exit List

This is the meat of the strip chart page. The strip chart shows information about each exit and the spaces between exits.

Interchange Descriptions

For each interchange:

• In the center is a visual diagram of the interchange showing all ramps that affect the mainline highway (any ramp that someone can follow to get onto or off of the mainline at that interchange). This diagram is also a link to the Terraserver aerial photo or topographic map of the interchange. The diagram will show what is in the Terraserver photo or map (some of which are quite old) unless I get newer information through road inventories, current exit list web sites or other correspondence. The color of the crossing roads indicates the type of road as follows:
  • Blue -- Controlled access highway - 1 line for a super-2, 2 lines for a standard freeway, additional line for each median separated set of special purpose through lanes (express lanes, HOV lanes, etc.).
  • Red -- Urban arterial, rural primary through routes - 1 line for non-divided, 2 lines for divided.
  • Green -- Urban non-arterial, rural secondary through routes
  • Gray -- Other through or any non-through routes
• On either side are the names/numbers of the roads/highways that leave the interchange on that side. The color of the name corresponds to the color of the line in the diagram and will be aligned with the appropriate line. Occasionally, names in black are used to identify place names near the interchange.
• Outside of that are the exit descriptions for the interchange.
• On the far left side is the exit number (or list of exit numbers on rare occasions) for the exits shown in the interchange description. There may be other numbers prefaced by 'mp' which are mileposts for consecutively numbered exits or temporary exit numbers. If there is a known error in the interchange description, an 'ERR' error tag with a link to the known errors page entry will appear underneath the exit number. If there is an open question in the interchange description, a '?' open question tag with a link to the open questions page entry will also appear underneath the exit number.

Two different interchanges with exit and entrance ramps that intertwine will usually be shown on the same interchange diagram. If these cases have a milepost between crossing roadways, I will show both exit numbers in the interchange description. All interchanges with crossing roads between two consecutive mileposts will also be shown on the same interchange diagram. If the highway uses milage based exit numbering, all of the exits will have the same number with a letter suffix. I use only the number part in the interchange description. For highways that use consecutive exit numbering, I show all exit numbers for exits shown in the interchange diagram.

Exit Descriptions

The exit descriptions are not meant to copy what is on the highway guide signs placed at each exit ramp. Each exit description (gray box) represents one exit ramp on the interchange (there are no descriptions for entrance ramps shown). The text in the exit description box describes what is reached by taking the exit ramp. These include highway numbers and names, road and street names, city and town names and points of interest. Items in bold print show the things that are immediately reached at the end of the ramp. Below these is a rectangle containing arrows (). This is a lane depiction showing which lanes are through lanes, which lanes exit and where the gore is in the lane structure. The exit description will ALWAYS be for the turning lanes depicted. There will also be a rectangle containing the word 'GO' and an arrow () if the crossing highway is another interstate highway. This is a link to the crossing highway's strip chart pages that takes you to the same interchange in that strip chart. This also shows up at state line strip chart ends and takes you to the next state's strip chart page for the highway. If there are differences between the exit diagram and the Terraserver picture reached through the diagram link, there will be a line explaining this in parenthises describing the difference just above the lane depiction. For many interchanges, there is only one exit description (such as the left side Mill Plain Blvd exit description above for exit 28) indicating that there is only one exit ramp with no follow-on ramps.

Multiple exit descriptions are used to indicate more complicated ramp structures. Looking at the left side WA-500 (exit 30) exit description box group above, the left-most exit description box indicates the exit onto the C/D ramp (see the exit diagram) on the left side of the mainline highway. The next 2 exit description boxes to the right (marked 'West' and 'East') describe the two exit ramps coming off of the C-D ramp. Exit descriptions aligned like this, with one exception, always indicates ramps off of the same feeder (whether it be the mainline freeway or another ramp). The one exception is for median separated lanes, such as express lanes, which have exit descriptions vertically separated with the first line in the first exit description in bold italics indicating the lane group described. The top-most exit description indicates the top-most ramp in the diagram. This means that you read the boxes in order from top to bottom on the left side ('West' is the first ramp you come to, 'East' is the second) and from bottom to top on the right side ('East' is the first ramp you come to, 'West' is the second). To the right of the 'West' exit description are two exit descriptions marked '4th Plain Rd' and 'WA-500 West'. These indicate the extra ramp on the upper left part of the diagram. This horizontal placement indicates which ramps must be taken to reach this place. All exits indicated by exit descriptions to the left must be taken to reach an exit indicated by the desired exit description (to reach the '4th Plain Rd' exit ramp, you must first take the 'WA-500' exit off the mainline onto the C/D ramp, turn off the C/D ramp at the first exit marked 'West' and then turn right at the next split).

Between-Interchange Information

Between interchange descriptions is a description of things passed between the interchanges. These things include:

• An arrow indicating the direction of travel (and the direction you should vertcally read left aligned exit descriptions)
• The number of miles between the interchanges in bold print (to the nearest mile) [not present if the previous interchange had no exit ramps in this direction]
• The total number of miles from the end of the highway 'behind' you in bold print [not present if the previous interchange had no exit ramps in this direction]
• The number of lanes over the majority of the space between the interchanges in bold print
• Any rivers
• Any state and/or county lines
• Any international boundaries (at the end of some strip charts)
• Any multiplexing highways
• Any speed zone changes in italic print
• Any changes that occur in the year of the Terraserver photos linked to through the interchange diagrams in italic print
• Any other notable facts for this segment of the highway

Site Navigation

• Get strip chart by highway then state
• Get strip chart by state then highway
• Sources

• Return to strip chart project home page
• Return to my home page

Contact Information

Corrections and suggestions may be submitted here.

url: http://home.comcast.net/~andytom/Highways/htmlScripts/index.html
last revision: 31 DEC 2005