Water planning is an important logistical and risk management concern of road races. Until now event organizers have used guesswork and experience to estimate water needs on the race course. The Road Race Water Planner (RRWP) app© is the first to provide a strong scientific basis for easily and accurately estimating water needs, thus providing rational and actionable information to simplify logistics and improve risk management. The app can also reduce the environmental and economic impact of water planning while optimizing runner health and performance.
The RRWP uses a patent pending H2Q TechnologyTM for accurately estimating individual exercise sweat losses and applies it to solve for the large individual variations in sweating that create uncertainty for group water planning. Group estimates are ultimately obtained from a weighted composite RRWP population of more than 9 million marathon runner finishing times. Large sample estimates from individual races reflect the theoretical RRWP population prediction distribution with fidelity in accordance with central limit theory. Simply input air temperature, the number of runners participating in the race, the race distance, and the number of water stations on the course. RRWP solves for the total number of gallons of water needed on the course, the number of gallons per fluid station, and the total number of cups and cups per water station (assuming 4 fluid ounces per cup).
RRWP is a complement to the experience of event organizers and will greatly help narrow the uncertainties of water planning related to changes in weather, participant numbers, and race distance. And because it provides an accurate estimate of average runner sweat losses, it minimizes the potential for irresponsible drinking behaviors.
Accurate water estimates also reduce waste and costs. RRWP is consistent with growing sustainability initiatives aimed at incorporating environmentally and socially responsible practices into the operational planning, preparation and execution of road races.

What’s New

Version 1.2

No new features in this version. A few keywords have been added for better searchability of the RRWP App on the iTunes store.


Sports Science Synergy, LLC
7.9 MB
Health & Fitness

Requires iOS 9.3 or later. Compatible with iPhone, iPad, and iPod touch.



Age Rating
Rated 4+
© 2017 Sports Science Synergy, LLC


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.