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Below are links to various noncommercial river trip support documents and/or web pages that may help you when planning your trip.
Noncommercial River Trip Support Documents
Lottery and River Use StatisticsGrand Canyon River Statistics
Lottery Mechanics and DataWhen applicants apply in a noncommercial river lottery, they can see exactly how many points/chances their lottery application will get in that lottery. Each point/chance in a lottery is equivalent to having a tiny copy of an application thrown into a hat. The noncommercial river system randomly picks an application from the hat, and that application is considered in full before the system continues on to the next drawing from the hat. In practice, this starts with the noncommercial river system creating as many copies of a lottery application as the application has points (so 5 copies for 5 points/chances). Once this has been done for all applications, the system randomly shuffles the entire collection of applications and saves them in a new, random order. Then, using that new, random order, the system goes through each application and considers it in its entirety. To make this more understandable, here is a very simple example. Suppose you and only one other person applied in a lottery. Let's say your application (A) had 4 points/chances, and the other person's application (B) had 3 points/chances. When the lottery is run, the system would create a collection with 4 entries pointing to application A (one entry for each point/chance the application was to receive) and 3 entries pointing to application B. The system would then shuffle the entire collection of all 7 entries, assign a new, random order to it, and save that new order. Let's make A's random order 2 | 3 | 5 | 7, and B's random order 1 | 4 | 6. Now launch dates would be assigned. The system would start with the number 1 spot, pull up application B, and consider that application in its entirety. This means the system would consider all of B's launch dates in the preference order listed and award the first date, if any, that is available. In this case application B is awarded their first launch date choice. The system would now go to the application in the number 2 spot (application A). Just like before, this application would be considered in its entirety, going through launch dates in the preference order listed and awarding the first one found to be available. The system next goes to the application in the number 3 spot (application A), sees that application already won, and goes on to the number 4 spot (application B). This would continue until all the spots in the random order had received consideration. A lottery application is only marked as unsuccessful if all preferred launch dates listed on that application were unavailable when the application was considered. When Winners Immediately Cancel: When a follow-up lottery winner cancels without paying the lottery deposit, the Grand Canyon National Park River Permits Office will either release the unclaimed launch date through a subsequent lottery or, if the launch is soon, contact runners-up from that lottery and award the date to the first runner-up who replies back accepting the launch date. The River Permits Office makes these contacts using a runner-up list generated by the system for the particular lottery and launch date. This list uses the same random order that the lottery used. Trip leaders who won a date in the lottery are not included on the runner-up list, even if the now available date fell higher on their preferred list of dates than the date they won. The data supplied below comes from noncommercial river lotteries run between 2007 and Jan-4-2024. For additional information about lottery chances/points and answers to many other questions, please see our Frequently Asked Questions document. To contact the River Permits OfficeYou may call us directly at 928-638-7884 or 800-959-9164 (Mon-Fri). FAX number is 928-638-7844. You may also write to:
Additional river info can be found at the following webpages.
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Last updated: November 8, 2024