CWEA Awards Santa Clara’s Visala Tallavarjula the California SJWP Second Year In-A-Row

The Stockholm Junior Water Prize (SJWP) is considered the world’s most prestigious award presented to a high school student for a water-research project. The Water Environment Federation (WEF) has coordinated the U.S. competition since its inception in 1997, and partners closely with their Member Association (MA) to execute the program.

Initially a paper competition from 1997-2001, the eligible projects were gleaned from the regional and state international Science and Engineering Fair (ISEF) by Member Association (MA) appointed judges. In 2002, the MAs sent their state winners to the first onsite event that was jointly hosted in Dallas, TX by WEF and the Water Environment Association of Texas. The event was modeled after the international event, including three days of competition and social activities, and up until 2013, was the U.S. model.

CWEA is excited to announce that Visala Tallavarjula of Santa Clara, California will once again represent the state of California for her project titled, “Statistically Designed Experimental Optimization of Root Zone Water Delivery Using a Low Cost Surface Drip Micro-irrigation Method for Regions Suffering from Drought.”

Visala was California’s winner in 2016 and was invited to speak at CWEA’s Annual Conference in Palm Springs during the Engineering and Research Committee Luncheon about her project on Sub-surface Irrigation.

The winners will go on to compete in June with the national winner moving on to the international competition in late August. The competition is open to public, private, or independent high school students in grades 9-12, that have reached the age of 15 by Aug. 1 of the competition year, and have conducted water-related science projects.  Judging criteria are the same as the international competition and include ratings for relevance, methodology, subject knowledge, practical skills, creativity and paper/presentation.

ABSTRACT: Statistically Designed Experimental Optimization of Root Zone Water Delivery Using a Low Cost Surface Drip Micro-irrigation Method for Regions Suffering from Drought

Visala Tallavarjula

About 70% of global food production is from arid regions, accounting for more than 70% fresh water withdrawal. The purpose of this project is to deliver water from the emitters of surface drip quickly to the root zone before it can evaporate. Cylindrical insert is optimized using statistical Design of Experiments. Inserts of 2 cm diameter filled with sand are buried in soil under the drip emitters. Water infiltrates through sand at much faster rate compared to the rate of evaporation from soil surface. Once water gets to sub-surface regions (> 3cm of depth) evaporation loss is suppressed since wet soil is not exposed to wind and sunlight. Also a 3 cm layer of Perlite and peat-moss is used as top soil bed since it has proven to improve water retention even further. Field tests were conducted at Jacobs Farm in San Jose. Prototype gravity fed micro irrigation system was built. Water conservation (29-60%) was demonstrated with multiple plant types. These low cost enhancements can improve micro irrigation efficiency and reduce water foot print of agriculture in arid regions.

See full paper.


West Yost Associates’ support for the SJWP competition will allow CWEA to advertise the program more widely to California high school students, provide travel support for the winner and allow the development of new competitions to promote interest among high school students about California’s water quality and water treatment technologies.

West Yost Associates was established in 1990. The firm’s focus has been exclusively on water, wastewater, and stormwater projects with the objective to provide a higher level of client service around this focused area of technical expertise. The firm culture is deeply rooted in providing high quality work, superior client service, and technical expertise.

Leave a Reply

Your email address will not be published. Required fields are marked *