The Bureau of Reclamation favored the Echo Park site over Glen Canyon, because its narrow canyons and high elevation (more than , as compared to at Glen Canyon) would lead to less evaporation. It said that building Echo Park Dam and a "low" Glen Canyon Dam would save of water per year over a "high" Glen Canyon Dam (which was ultimately the version to be built). While studying the figures, Brower discovered that the difference should be no more than . Although it is unclear whether the discrepancy was due to a miscalculation or intentional manipulation, Brower said "it would be a great mistake rely on the Bureau's figures when they cannot add, subtract, multiply and divide."