Monday, May 23, 2011

New ET research site online!

I recently initiated a new ET-based irrigation controller research site at a homeowner property participating in Miami-Dade Water & Sewer’s Water-Use Efficiency Program.


We began the day with the ambitious aim of visiting 5 properties in 7 hours: 2 new installations, one re-installation and 2 repairs.

First up was a property where the soil water sensor add-on device had quit reading moisture a week earlier. This add-on device consists of two components (controller and sensor) and is designed for pre-existing digital systems. The two components use existing wiring to communicate and prevent scheduled irrigation events when soil moisture is above the set threshold.

We replaced the sensor in the field (buried horizontally 3-4 inches under the turf) and protected wiring connections with grease caps and a junction box.

We then installed a new controller at the timer, initiated communication, and tested for irrigation prevention and bypass.

Since this site is part of the comparison study, one of the study zones always irrigates on schedule.


Our next stop was a property with a pre-existing digital system that elected to participate in the ET-based controller study. Because valves are already part of this system, our tasks were limited to:

- installing a water meter on the system's mainline for water-use data purposes

-replacing a decrepit anti-siphon valve (this device protects the potable water lines from irrigation system contamination) with a new one

- replacing the current timer with the “smart” controller that irrigates using self-generated ET information and irrigation zone specifics

- mounting the weather station in an area unobstructed from exposure to the elements

This 7 zone city water system with rotor and rotary zones and varying shade factors in its landscaping should provide great insights into ET-based controller water-savings potential.

…when you’re having fun

At day’s end, we had completed work at four of the five scheduled sites. This included the above work, some zone redesigning at an ET site and some rotor repairs at an older site. Next month promises more installs as 5 properties are in line for the ET study! Stay tuned.

Wednesday, May 11, 2011

U.C.U: Saving gallons by the thousands!

Over the past several weeks, Miami-Dade Extension's Urban Conservation Unit (UCU) has engaged in some concrete water-saving work. The following is a brief account of two recent experiences in the field: aiding a homeowner in distress and facilitating another's journey to efficient irrigation.

Golden Beach

A few weeks ago a homeowner contacted Extension daily over several days to complain about his exorbitant water bill and non-responsive municipal entities who had failed to help him diagnose and rectify his problem.

UCU to the rescue! Our most immediate obstacle - the 1.5 hour trek to the verdant lawns of Golden Beach, which we could not make without first scheduling other site visits nearby.

In the meantime, we debated amongst ourselves what the property's problem might be. Was it a main break gushing somewhere between the water meter and the irrigation system? Or was it simply a large break in the system easily addressed by turning the system off? We settled on the former and received permission to shut off the water meter should it be necessary.

Seven days later, we arrive. We find the meter perfectly still, immediately eliminating the main break possibility.

The assessment begins: digital system, 8 zones, city water and featuring high volume spray-head heavy zones on a property with scant turf and thick with low-maintenance plant life.

3 of the 8 zones have large breaks and the average zone GPM is in the 30s. Add a haphazard watering schedule (4 days/week) with excessive run times and the weekly expended total is 40,000+ gallons!

We calculated this on the spot for the homeowner's mom and she granted us free reign toadjust the system. We dropped watering days to the mandatory 2 days/week, turned off zones with breaks and reduced run times on the others and the savings added up to 36,000 gallons!

North Miami Beach

During system assessments our favorite recommendations include: going digital at the timer and valve level, adding low volume nozzles to spray heads, and pulling spray heads in favor of drip line or other low volume irrigation in shrub zones. Abide by these precepts and water savings are guaranteed!

In early March we assessed a property in North Miami Beach for a homeowner at wits end with his high water bills.

His system: mechanical, 6 zones, spray-head heavy and dousing shrubs with sprays.

We discussed his system's failings with him, suggested how he might remedy each, and went on our way to the next appointment.

A few weeks ago, we had the opportunity to revisit this property and see most all of our recommendations in action! Digital replaced mechanical, 6 zones were reduced to 4, spray heads had low volume nozzles added and the shrub zone is now watered only with a soaker hose!

While we were pleased to see a homeowner follow through with efficient practices, he was ecstatic, going on and on about how his water use had dropped by 20,000 gallons and he had retrofitted the system with the billing period already underway. The true measure of his water savings awaits!

Educating and conserving

Sometimes in the day-to-day grind from one property to the next (from one wrecked, or poorly designed system to the next) one can get the impression that all of our best efforts fall on deaf ears. Contractors and homeowners listen, perhaps learn, but fail to act. These recent experiences, however, help demonstrate that when the stakes are high and the public is receptive, an outfit like the U.C.U. can make a real impact.

Monday, May 9, 2011

Dr. Richard Carey's dissertation research

Congratulations to Dr. Richard Carey as he has published a very interesting paper in Ecological Indicators 11:1093-1104. The title is 'Land use disturbance indicators and water quality variability in the Biscayne Bay Watershed, Florida'. If you have time, look it up! It is an excellent example of good research. Richard is currently working in New Hampshire- hopefully he will post some pictures and some of his current research!