SWES Student Seminars

Speaker:
Brittany Choate and Samendra Prasad Sherchan

Speaker Title:
SWES M.S. and Ph.D Students

Event Description:

 Evolution of the Roosevelt Water Conservation District: Lessons Learned from the Agriculture to Urban Community Transformation
The Roosevelt Water Conservation District (RWCD) has been responsible for managing the distribution of irrigation water to 40,000 acres of agricultural land throughout portions of Mesa, Gilbert, and Chandler, Arizona since 1920.  Each of these communities has seen tremendous population growth in recent decades requiring the RWCD to adapt to its more urban surroundings. To do this, RWCD has entered into water sharing agreements, made land acquisitions, changes to their Bylaws and worked with each community to accommodate the increased municipal water needs. Though each party entered into these agreements with good intentions, multimillion-dollar challenges and years of litigation resulted between the communities and RWCD; current relationships between these groups reflect the positive and negative experiences RWCD had with adapting to its service area’s population growing pains. These tested relationships now serve as an example of what may happen to similar irrigation districts caught in today’s ever-changing world of population growth and agriculture to urban conversion. This project aims to gather information from the multifaceted parties involved in the RWCD agreements, determine what led to the less than ideal results, and propose recommendations for how similar transitioning communities can avoid the same challenged faced by RWCD.

Inactivation of MS2 by advanced oxidation process
Ultraviolet light(UV) in combination with hydrogen peroxide (H2O2) has the ability to generate hydroxyl (.OH) radical which plays a vital role in destroying contaminants. The inactivation of coliphage MS2 using UV light in combination with H2O2 was studied to assess the importance of this process for virus inactivation during water treatment. We have used cultural and molecular methods to document the destruction of MS2 in real-time. Pilot-scale experiments were performed using the Trojan UVSwift SC reactor from Trojan Technologies. MS2 was inactivated by more than 5 log10 with UV radiation whereas quantitative PCR showed only a 2 log10 reduction  in viral RNA copy number. By the addition of H2O2 in the UV disinfection step, enhanced MS2 inactivation occurred with more than a 7 log10 reduction in plaque counts and a corresponding 3-4 log10 reduction in qPCR results.

Refreshments at 2:40 pm
 

Sponsors:
Soil, Water and Environmental Science