Civil Engineering ETDs

Publication Date

Summer 6-24-2019


Accurate tracking of open-water evaporative losses, one of the largest consumptive uses of water in the Southwestern USA, is increasingly important with anticipated climate shifts toward longer and more severe droughts. A new open-water evaporation technique, the Collison Floating Evaporation Pan, (CFEP), was tested on Cochiti Lake, New Mexico, USA for one year with objectives being: identify the limitations and potential solutions to evaporation techniques; deploy, test the reliability, and validity of the CFEP and evaluate uncertainties in standard evaporation techniques; and improvements over prior evaporation techniques. The CFEP provided reliable evaporation measurements during sustained winds greater than 20 m/s. The accuracy of the CFEP was validated with an averaged percent difference of 1.72 of actual. The CFEP provided more accurate evaporation measurements than the five methods it was compared to with the Class A Pan underestimating evaporation by 910 acre-feet from May 13 through November 30, 2018.


Evaporation, water management, water resources, open-water evaporation, Class A Pan


U.S. Bureau of Reclamation

Document Type




Degree Name

Civil Engineering

Level of Degree


Department Name

Civil Engineering

First Committee Member (Chair)

Mark Stone

Second Committee Member

Julie Coonrod

Third Committee Member

Jan Boll

Fourth Committee Member

Ricardo Gonzalez-Pinzon