Obstacle Departure Procedures (ODPs)
ODPs come in two forms, textual and graphic. When the textual ODP is considered to be “complex” (lots of turns or weird instructions), the FAA will also make it available in graphical form. It’s important to remember, that although there is no regulation forcing you to fly a published ODP, it is very wise to do so as those are flight tested routes proven to be safe. Flying off on some random vector assigned by ATC is not 100% guarantee of safety.
Where do you find them?
ODPs can be found in the “TAKEOFF MINIMUMS” section of the chart supplement.
Textual ODPs
Here, nestled in with the takeoff minimums (that do not apply to part 91 operations, but are a really good idea to follow, or even follow more strict minimums for departing IFR) and TAKEOFF OBSTACLE NOTES, you’ll find
the applicable DEPARTURE PROCEDURES. Now not all runways at an airport may have such a procedure. If there is not an obstacle that penetrates the protective climb gradient, the FAA will not publish a procedure for that runway (remember that they are assuming you have at a least a 200′ per nm climb ability, if your airplane can’t do that, all bets of protection are off).
For KVNC, departing runway 31 the ODP instructs you to climb on heading 305 degrees up to 1,500′ msl before making any turns. Looking upwind of runway 31 in Venice, we can see the idea behind this (the towers east of the extended center line of runway 31).
Do ODPs really mater since they’re not regulatory? Well ATC is NOT responsible for your separation with terrain or other aircraft for that matter in Class G airspace, and not every clearance they give you will protect you even if you do have the 200′ per nm climb ability. The only way to be sure not to hit something is to fly a published procedure.
CASE STUDY:
Pilot in a Cessna 210 with over 700 hours in that airplane departs IFR out of KMVL from RWY 19, with a clearance from ATC of Direct CAM VOR. He and his two passengers die shortly after takeoff when he impacts rising terrain south of the airport. He did not fly the ODP for RWY 19 out of KMVL, nor did he note it in his remarks section of the flight plan, showing any intent to comply with it. Click Here to Read the NTSB Report
Remember: You are fully responsible for the safety of your passengers, yourself, people on the ground, and your airplane. Make the safe choice, spend an extra 2 minutes flying around the terrain to get to a higher altitude before proceeding on course, whether its IFR, MVFR, or even just night time or an unfamiliar airport. Better to waste 3 minutes flying than the last 30 years of your life.
How to File a ODP
Filing a SID is easy, filing an ODP isn’t really an option in the ROUTE section, but you can put it in the remarks section, and inform ATC when picking up your clearance that you intend to fly the ODP, then on the route they clear you for. Make sure the ODP doesn’t disagree with the route they assign you, if there are any conflicts (i.e. your clearance includes instructions “CESSNA 8MA, ENTER CONTROLLED AIRSPACE HEADING 090”), then looking at departing RWY 31 from KVNC that would not work (you can’t fly heading 305 to comply with the ODP, because ATC wants you on a heading of 090 when you reach 700′ agl). In this case, where the ODP disagrees with a ATC clearance, query the controller and consider using a different runway, getting approval to fly the ODP, or modifying the clearance (do this BEFORE you takeoff!).
Graphical ODPs
So ya know how I said above that ODPs come in two forms, graphic and textual? Well, good luck finding a Graphic ODP anywhere, even when the textual procedure is very complex. In fact, the lack of graphic ODPs is so great that NBAA actually wrote a formal complaint letter to the FAA about it back in September of 2006. 
Not much has been done on this front since that letter, other than more RNAV SIDs have been introduced into the IFR System. The trouble with RNAV SIDs is you need a legal GPS to fly them, so if you have only VORs (equipment “/U”), then you’re left out of all the fun. A good reason to get your airplane equipped with a certified GPS is the vast availability of RNAV SIDs popping up. They are both efficient, all come with a graphic representation, and guarantee you obstacle clearance!
When a graphic ODP does exist, you will see a note in the DEPARTURE PROCEDURE section that reads like this:
Click here to see an example of a Graphic ODP
Take a look here to the left at the textual ODP for KPUC in Utah. It’s fairly complex, yet there is no graphical depiction of it anywhere! Read and hope you understand what you are supposed to do.
Here’s and an example of an RNAV SID, it’s a bit easier to follow reading both the text and seeing it visually depicted where you will depart the runway from.