Executive Summary

The University of Texas at Austin’s Facilities Management initiated a comprehensive program in 2007 to develop and implement water conservation measures after a task force on sustainability was established. The goal: reduce domestic water use by 20% and at least 40% of total water use coming from reclaimed sources by 2020. During this project, it was determined the campus’ irrigation system lacked qualities needed to meet the new sustainability requirements. As a result, the system was upgraded to Calsense smart computer technology to monitor detailed water usage, detect and report daily irrigation problems, and provide the expertise to support staff in being effective in using the smart technology. Irrigation sprinkler heads were also replaced with more efficient, Hunter® MP Rotator® rotary nozzles and various areas of turf were replaced with drought tolerant plant material.

  • Consistent irrigation reduction of at least 66% since 2012
  • Over one million dollars in cost avoidance
  • Saving over 100-million gallons of fresh water each year

Challenges

An audit of the main campus irrigation systems was performed in 2008 by the general contractor, Water Management, Inc. with assistance from the City of Austin. The audit inventoried all irrigation control points with regard to water supply type, size, and location, and assessed the current irrigation systems’ scheduling and water distribution efficiency. The following issues were identified and analyzed to develop appropriate solutions:

  • Various controller products were unable to communicate with each other or to a central location
  • Irrigation distribution systems (sprinkler heads) were inefficient
  • Landscape Services staff could not automatically adjust watering schedules based on real-time weather conditions
  • Landscape Services staff could not accurately measure water usage
  • Landscape Services staff could not shut off water automatically when a leak or break occurred

How Calsense Helped

After test driving the product and consulting with Water Management, Inc.,  the University selected Calsense based on performance, data collection ability, ease-of-use, factory-direct training and support, and a 10-year warranty. In 2011, the University obtained funding for installing 104-controllers, along with ET gauges, tipping rain buckets, flow sensors, and master valves. Tracking gallon usage, detecting system breaks, measuring usable rainfall, and tracking water evaporation from the landscape to automatically calculate station irrigation minutes was underway. The Calsense system can be controlled from anywhere by laptop, tablet or smartphone. This allows shut down of the system if an unscheduled event occurs after hours, or troubleshooting a problem without sending an individual to the site. The controllers are equipped with radio modems and are communicated to through a HUB via Ethernet and radio, operating in the UHF 450-470 MHz band.

Results

The campus irrigation system was estimated to use 175 million gallons of water a year with 2009 as the base. In 2012 the campus reduced the irrigation usage by 66%, and repeated the same savings in 2013 and 2014. Due to the wet season in 2015, the campus reduced water use by over 75%. The ROI is calculated at three years.

Once the equipment was installed and collecting data, Landscape Services saw an opportunity to share this information with the campus. This created partnerships with academics:

  • School of Engineering – Using irrigation usage to design rainwater harvesting systems on campus.
  • School of Architecture – Analyzing the data to see which landscape material provides a sustainable design and will survive in the Texas environment.
  • Sustainability Department – Providing data to students interested in conserving water on campus.
  • Utilities – Providing data verification for comparing the City of Austin water meters to the billing received and to assist in finding possible leaks around campus.

In May 2012, the university formed a partnership with the City of Austin in piloting an alternative irrigation compliance program that gives a monthly water use allowance (“budget”) based on square footage. Currently, the city limits the number of days irrigation is permitted.  Since Calsense gathers and reports flow data and square footage to a budget, the city can use that information to determine if new requirements are attainable and whether the landscape can sustain the desired appearance. The university provides the city with the ease and convenience of receiving a database with all the campus water usage and comparison to city water budget requirements.

About

Ranked among the biggest and best research universities in the country, UT Austin is home to more than 51,000 students and 3,000 teaching faculty. Working together to change the world occurs through groundbreaking research and cutting-edge teaching and learning techniques. This university motto carried over with the implementation of computer technology for resource management and irrigation control, that knowledge with the students, the community and beyond.

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