Wednesday, April 25, 2018

Studying Irrigation Restrictions in Southwest Florida

Outdoor watering restrictions are one of the more common methods in Florida for curtailing irrigation. Most of the water management districts in the state recommend limiting irrigation during some portion of the year, usually during Florida’s dry season (November - April). Recently, UF-ABE alum Dr. Mackenzie Boyer published research which analyzes the effectiveness of irrigation restrictions - Water Conservation Benefits of Long-Term Residential Irrigation Restrictions in Southwest Florida. Read on for a selection of excerpts.

Dr. Mackenzie Boyer in presentation mode
Setting the Scene
Residential irrigation watering restrictions are often a standard water
conservation tool for US utilities, especially in the Southeast and
Southwest, where water resources are particularly limited and there
have been prolonged droughts. Water restrictions take various forms
throughout the United States. Most residential ordinances ban irrigating
during the hottest daytime hours (when irrigation water can be lost to
evaporation before it has a chance to be used by plants) and limit
homes to specific watering days. Some restrictions are voluntary,
while others are mandatory. Many have exceptions for newly
planted landscapes or handwatering. Despite the prevalence of water
restrictions, there is little published research on their effectiveness, and
research is generally limited to short durations or utility-wide averages

Study area in Southwest Florida
Irrigation restrictions in the Tampa Bay Water area offer a unique look into both long- and short-term restrictions as well as the behavior of individual customers. The goal of this study was to determine the effectiveness of long-term watering restrictions to reduce irrigation by individual single-family residential customers in southwest Florida. The primary objective was to compare each customer’s irrigation demand under two days/week and one day/week irrigation restrictions. Next, high, medium, low, and occasional irrigating groups were identified, and the high irrigators were mapped to determine whether there was a geographic component to irrigation behavior. Finally, the impact of a short-term ban on inground irrigation in Tampa was evaluated.

Figures 5 and 6 show both the benefits and shortcomings of
day-of-the-week water restrictions to reduce irrigation demand. The
figures show the mean (Figure 5) and median (Figure 6) monthly
irrigation demand and irrigation required of the four groups.
It is clear from the magnitude of the irrigation demand that the high
group irrigated regularly (3.2–5.6 in./month under two days/week
restrictions), whereas the occasional group irrigated little if at all
(<0.3 in./month). Therefore, the high group had a greater potential
for conserving. Irrigation demand for high irrigators was 10.2 in./year
lower under one day/week restrictions compared with two days/week
restrictions, whereas occasional irrigators’ irrigation was 0.3 in./year
higher (Table 2). Day-of-the-week restrictions were successful in
reducing irrigation demand of the highest users, but they may also
encourage some customers to irrigate.

Mean and median irrigation demand/required
Long-term water restrictions that periodically reduced irrigation from
two days to one day/week during the study period of 1998 through
2010 coincided with lower irrigation demand in southwest Florida.
Annual irrigation demand was 13% lower (11.3 in./year under two
days/ week restrictions to 9.8 in./year under one day/week restrictions),
while annual irrigation required was 3% higher (25.0 in./year under
two days/week restrictions and 25.7 in./year under one day/week
restrictions) during the period of the more stringent restrictions.
Throughout the region, customers’ irrigation demand tended to be
much lower than the irrigation required, classifying the region as a
whole as one of deficit irrigators. As a group, high irrigators’
(defined as having annual irrigation demand that exceeded the
irrigation required) irrigation demand as a depth was 20% lower
under the more stringent conditions, indicating that those who
irrigated most had the most potential for conservation. Additional
conservation potential existed for high irrigators, for which the
irrigation demand was still 56% above irrigation required under
one day/week restrictions. The primary focus of this study was
long-term water restrictions, but the brief ban on irrigation in
Tampa in April and May 2009 resulted in a substantially lower
irrigation demand as well.

The authors would like to thank the Southwest Florida Water
Management District and Tampa Bay Water for funding this research.

Wednesday, April 18, 2018

H2OSAV and Water-Use Data Visualization

We are in the age of big data. With respect to water-use, being able to access, analyze and visualize data is invaluable for both research and conservation program development. UF/IFAS State Specialized Extension Agent Dr. Nick Taylor uses data to help utilities increase water savings with H2OSAV. Dr. Taylor recently presented his work at the South Florida Water Management District Water Conservation Expo, where he agreed to an interview with IrriGator.

Dr. Nick Taylor, UF/IFAS State Specialized Extension Agent
Can you describe H20SAV?
NT: H2OSAV is a water-savings analytics and visualization tool. What we’ve done is put together a suite of software platforms that a utility can use to assess how their conservation programs have been performing in the past so they can begin to better target those programs to their customers - based on consumption patterns and property features - in a way that can help to increase overall savings. Another component of H2OSAV is data sharing between utilities about programs - how they perform, how to make them better and how to move forward to reach their savings goals.

Can you talk about how a data hub like H2OSAV can be useful for research?
NT: Well there’s the obvious data component - data availability, being able to merge and match that data with property appraisal and other open sources of data. In the past I’ve worked with a number of students of researchers from all over the country to gain access to utility data. And what we get is a group of collaborators who can start to evaluate research questions, maybe add ideas about how that data handling works well or not so well. That’s on the academic side.

On the county level we do have extension agents using this platform. Even though the primary data source has to come from the utility, in several instances the extension agent for the county is also using this. Alachua County is a prime example. Gainesville Regional Utilities has this service and both Alachua County EPD and the Alachua County extension agent use it. It’s very similar in Sarasota and hopefully we’ll be talking with other utilities we work with about access to those platforms for the extension agents there.

Right now is H2OSAV mostly focused around the Central Florida Water Initiative (CFWI) area?
NT: Yes. Part of the reason it’s focused there is that the state DEP is very concerned about that region. They have directed our attention to that region. We have good collaborators in that region and they have a very set goal that they need to reach. It’s very critical at this time. We’re certainly willing to branch out, but it gives us a contained area to really focus on.
Where is H2OSAV in its development? Is this something that is ready to be applied anywhere or are you still working on refining/perfecting?
NT: It has been deployed. There are utilities that are using it. It’s also under constant development where we have production versions, development versions and then we roll out updates, much the same as you would get an update to an app on your phone, or any sort of software.

Currently we have three software tools and they will be merged eventually into one tool that can do many many things. The bar is going to be set high in the future. We have a lot more work to do. What I really want to see is better collaboration between the utilities and that’s the main goal. If there is a next phase, or next step, we want to see some proof that this tool is actually helping and reducing water use.

Wednesday, April 11, 2018

Plot Study Comparing Different Irrigation Technologies For Turfgrass

By Kati Migliaccio

From 2015 to 2017, a plot study was conducted in Gainesville, FL, during the growing season. A weather station at the plot site collected weather data and water meters recorded the amount of water applied to each plot. Plots contained established Bermudagrass and were irrigated with four quarter-circle pop-up spray heads.

Figure 1. Picture of turfgrass plots at University of Florida.

Eleven different irrigation technologies were used to schedule irrigation: time-based treatment without a rain sensor (WOS), time-based with a rain sensor (WRS), time-based with a rain sensor and a 60% deficit (DWRS), Smartirrigation turf app (APP), Smartirrigation turf app with seasonal water conservation (APPSWC), Baseline soil water sensor (BAS), Rain Bird soil water sensor (RBD), Toro soil water sensor (TOR), Hunter Solar Sync ET (ETH), Rainbird ESP SMTe (ETR), and Weathermatic ET (ETW).

Figure 2. Data collection at the turf plots at the University of Florida Agricultural and Biological Engineering Department (Bernard Cardenas-Laihacar and Ian Hahus pictured)

Results showed that all irrigation scheduling method tested produced water savings as compared to WOS treatment. Average water savings for the soil water sensors ranged from 50 to 61%, for the ET controllers ranged from 19 to 62%, and for the Smartirrigation apps 51 to 64%.

In this plot study, we investigated the use of the seasonal water conservation feature in the Smartirrigation Turf app (APPSWC) where irrigation schedules were provided at a 25% deficit if rainfall exceeded evapotranspiration (ET) the five previous days. This strategy helps reduce irrigation when rainfall is expected to occur and to contribute to plant water needs. During the three years of the study, adding the seasonal water conservation component to the APP schedule resulted in additional water savings. The average water savings over the three years as compared to the WOR treatments for the APP and APPSWC were 51% and 64%, respectively.

During year 2017, a modification was made to the soil water sensor treatments where irrigation was split between two events, a morning and afternoon event. Interestingly, this strategy resulted in only 20% or less events of full irrigation for the three treatments (Fig. 3)

Figure 3. The percent of irrigation events that were full irrigation (pink), percent of irrigation events that were half (green), and percent of irrigation events that were interrupted (gray) for 2017 soil water based sensor treatments

Useful Add-ons
Our results suggest that coupling an irrigation technology with another scheduling feature, such as split irrigation events or irrigation deficits, provide for additional water savings without impacting turf quality. These two add-on features would be useful to implement in locations where rainfall significantly contributes to plant water needs.

For more information on using technology for scheduling irrigation - contact Dr. Kati Migliaccio or Dr. Michael Dukes from the Agricultural and Biological Engineering Department. Additional information is also available in the UF/IFAS EDIS system.

Wednesday, April 4, 2018

Three Questions About Smart Irrigation Technology

April is Water Conservation Month in Florida. A large part of using water efficiently day to day includes outdoor water-use. Next week UF-ABE Professor and Extension Specialist Dr. Michael Dukes is participating in an irrigation technology training in collaboration with Tampa Bay Water and Florida Irrigation Society. Dr. Dukes’ team is usually involved in several of these technology trainings every year. To mark the initial event of 2018, he agreed to answer three preview questions for IrriGator.

What is exciting right now in the world of smart irrigation technology?
MD: There are many options. There are over 800 models of weather-based (evapotranspiration, ET) controllers that have the EPA WaterSense label. Soil moisture sensor (SMS) based controllers don’t yet have a label but there are several of those on the market as well. Exciting new developments are that many ET controllers have remote connectivity. Some are completely controlled by your smartphone. These devices offer many features. Unfortunately, most haven’t been tested in Florida and I understand from field reports that not all are adapted to our climate with intense local rainfall. We always recommend some sort of on-site rain sensor such as an expanding disk rain sensor.

I often find practicioners view weather-based and soil sensor-based irrigation technology as rival options. How do you address this perspective?   
MD: They can be seen this way, but each have their place. I believe the advantage of the SMS is that it integrates rainfall to control the system. Not all ET systems do this well (see previous comment). On the other hand for a one sensor SMS system, the location of the SMS is critical since it controls whether the system irrigates or not.

Your group does several trainings like this during the year, what can an attendee expect at the April event?
MD: We’ll review how smart controllers work, both ET and SMS, and why water conservation is important, and some things to be aware of on how to properly install these devices. We’ll also introduce other types of conservation devices such as pressure regulating spray heads, check valves and flow reduction - technologies such as pressure regulation that aren’t new but in the case of pressure regulation a new EPA WaterSense label is available. We are relying on vendors to present hands-on for their particular products.

Wednesday, March 28, 2018

Third Time's a Charm: An Urban Landscape Summit Report Back

By Michael Gutierrez

March 2018 marked year number three for the UF/IFAS Center for Landscape Conservation and Ecology Urban Landscape Summit. Arguably the best summit to date, this year’s event included informative and sometimes surprising insight from experts actively involved in developing solutions for urban landscape issues in Florida. UF/IFAS Miami-Dade Florida Yards and Neighborhoods (FYN) Coordinator Laura Vasquez traveled from South Florida to Gainesville to attend the event and agreed to share her summit experience with IrriGator.
Can you tell us about the work you do as Miami-Dade's FYN Coordinator?
LV: Our program encompasses three different sections: the Florida-Friendly Landscape portion of FYN, the irrigation portion (which is the Urban Conservation Unit) and also the rain barrels in schools program. I coordinate different events with the staff and work in each of the sections to help achieve program goals and teach landscape sustainability.

What was your primary motivation behind attending Urban Landscape Summit 2018?
LV: My primary motivation is learning about all these issues and solutions affecting urban landscapes and trying to apply them to our program in South Florida.
Was there any presentation(s) that really surprised you this year with new/original information?
LV: The presentation that stood out for me was the soil and tissue testing for Florida turfgrasses talk by Dr. Travis Shaddox from Fort Lauderdale REC. He talked about how much of the tissue testing for turfgrass is void. When someone does a tissue test, they receive a report that offers recommendations on how much fertilizer should be applied. He explained how there hasn’t been much research for establishing ranges for fertilizer application. So now Dr. Shaddox is working on establishing ranges of what should be applied based on tissue test results.

The fact that this is just now being addressed was surprising to me. This new insight suggests that recommending any kind of fertilizer use based on test results is not something we should continue to do.
Did you learn anything that you feel you can immediately apply to your work in Miami-Dade?
LV: With respect to the previous question definitely. Don’t be so quick to recommend soil/tissue testing since the usefulness of results are in question. In addition, researcher Bernard Cardenas presented a study on how quickly rain sensors dry out. According to his work, on average rain sensors dry out within 24 hours. For me this indicates that rain sensors are not the best option.
Miami-Dade Extension's Laura Vasquez conducts an FFL certification 
That’s fascinating, given that rain sensors are often the simplest/most practical option for preventing unnecessary irrigation. So what’s the alternative?
LV: For now, we’ll continue to push weather-based irrigation controllers/cloud-based controllers and shy away from rain sensors. Many homeowners depend on rain sensors but having this confirmation that they dry much faster than moisture in the soil was kind of surprising.

Your team has been consistent about attending the summit every year. What would you say to anyone working in your field that has been thinking about attending but hasn't yet?
LV: The best advice I would give is that if you really want to expand your knowledge of landscape sustainability, irrigation technology and on-going research that’s happening at the University - not only by professors but also students, so many students presenting posters with new ideas - this summit is one you should attend. There are opportunities as well to network with the people that are initiating all this work - one-on-one contact with top researchers in landscape sustainability and irrigation.

Tuesday, March 6, 2018

Previewing Urban Landscape Summit 2018

The 2018 Urban Landscape Summit is next week. It’s a rare treat to pack so much relevant Florida green industry insight in just two days of programming. A quick scan of the agenda reveals integrated pest management experts, turfgrass science experts, academic and municipal water-use experts as well as some great student poster topics. The UF/IFAS Center for Landscape Conservation and Ecology (CLCE) is the organizing body behind the summit. CLCE Director Dr. Michael Dukes agreed to an interview with IrriGator to preview the event.

This is the Urban Landscape Summit’s 3rd incarnation. Other than the underlying urban landscape aspect, is there a theme to this year’s programming?

MD: The past two years have been heavily focused on water issues. This year we still have water since it's such an important issue in landscapes but we also have topics just as important such as invasives and pests as well as homeowner insights. In addition, we have a nice diversity of topics being presented by graduate students.

Do you have any specific presenters or topics you are excited about or looking forward to?
MD: I’m looking forward to the entire conference but especially our keynote speaker, Timothee Sallin, who is the President of Cherrylake - once a traditional nursery but now vertically integrated to provide management and maintenance of their installed horticultural material.

Also, I really enjoy the 5 minute lightning round presentations. They give just enough information so I can tell whether it is applicable to me and if I need further discussion with the presenter.

This year the second day of programming is comprised of In Service Trainings (IST), any insight on this new focus?
MD: Due to IFAS budget cuts last year, fewer resources were available for ISTs, thus we sought to capitalize on the fact that much of our audience are extension agents and are already traveling to the summit. As a result, in addition to the summit been a formal IST, we have two other ISTs the second day taught by CLCE faculty.
Michael Dukes at the UF/IFAS Landscape Unit (image UFABE Blog)

For someone who works in an urban landscape-related field and is on the fence about attending, what is your best pitch for participating?
MD: The information presented at the summit is cutting edge research and extension information that can immediately be used by practitioners. In addition, this is an opportunity to meet faculty and county agents working in this area.

The 2018 Urban Landscape Summit takes place March 14-15 on the UF campus in Gainesville, FL. Register here.

Tuesday, February 27, 2018

Reporting Back from Water Institute Symposium 2018: An Interview with Bernard Cardenas

By Michael Gutierrez

For those of us working in water-use, UF Water Institute's 2018 Symposium (WIS) in early February marked a highlight of this year thus far. Experts, researchers, practicioners and students gathered in Gainesville for two days of presentations and panels covering the spectrum of water research. As someone who focuses on water-use efficiency outdoors, I was especially heartened by consistent references to landscape irrigation as a great, untapped area for water savings. IrriGator caught up with Symposium presenter and attendee Bernard Cardenas to further explore this idea and WIS 2018.

Both the opening and closing symposium plenaries alluded to how much potential there still is for outdoor water savings. What are your thoughts on this? How do you feel your presentation addressed this idea?
BC: Yes. There is high potential for water conservation still. There are new approaches not only with smart irrigation technologies but also Florida-Friendly Landscapes. That program is doing good things. In addition, Orange County Utilities for example is doing sprinkler nozzle replacements and rain sensor cost-share programs for better efficiency and preventing unnecessary watering.

What I presented was about testing smart irrigation controllers in the real world with the OCU Project. After five years we still have fantastic results with this technology - 32% water savings with weather-based timers and 43% savings with soil moisture sensors. One interesting fact I found from the plenaries is that more than 90% of new construction, single-family homes, come equipped with automated irrigation - something that was not so common 30 or 40 years ago. This puts a lot of pressure on utilities to provide water, so there is real potential for savings there.

There were dozens of presentations during the symposium. Can you talk about one or two you attended that really surprised you with either ambition or new insight?
BC: I was really impressed with Nicholas Taylor, state specialized extension agent, and his H2OSAV data hub. He is mapping data by home and neighborhood showing green space, water use, etc. So there is macro data and micro data. You’re able to see water use by neighborhood and filter for high irrigators. Really impressive.

Dr. Migliaccio’s talk was also interesting, more indication that wireless technology and wireless capability is the future. Your phone or mobile device is becoming not just your computer but your remote control for everything including irrigation in both landscape and agriculture.
The WI Symposium happens every two years. Do you feel it’s useful to have cross disciplinary water experts get together this way?
BC: Absolutely. For me it’s the only conference I’ve been to where the main players working in water, not just conservation but also water quality and coastal issues, get together to present/discuss about water in a holistic approach. I think it’s fabulous. There’s discussion among experts and academics and even feedback from the public. For anyone who attended the closing plenary, you saw members of Our Santa Fe River show up during the question and answer time and raise real, end-user concerns to the panel.

Can you talk about any research you’re working on this year that may tie into the theme of “Shaping Our Water Future?”
BC: Yes. Two things. We’re working on analyzing data supplied by Orange County Utilities generated from their rain sensor cost-share program and nozzle replacement initiative. So we’re looking at pre-/post-implementation there. And we’re also comparing those participating homes to their neighbors and also to the net irrigation requirement to analyze whether irrigation is below, matches or exceeds what is necessary to keep a healthy landscape. This kind of analysis is helpful so that utilities can determine whether or not their investment in conservation programs really yields results.

We are also going to begin doing additional work testing pressure regulating sprinkler spray bodies, as well as bodies with check valves and also the "x-flow" device that some sprinklers have that plug water flow when the nozzle goes missing - all efficiency enhancing features that help save water outdoors.