Tuesday, December 5, 2017

A Closer Look at Rapid Infiltration Basins

One of the projects I work on keeps me regularly visiting the Turfgrass Research Envirotron during summer. This summer the Envirtron’s outdoor area was a bevy of activity and building. Upon inquiry, Envirotron Biological Scientist Natasha Restuccia informed me that the build involved a rapid infiltration basin trial and that Dr. Travis Shaddox was the researcher to speak to for more. A few weeks later during a campus visit, Dr. Shaddox agreed to an interview with IrriGator about the project.

Dr. Travis Shaddox
What is the objective of this study?
TS: The project is funded by Southwest Florida Water Management District. The objective is to determine how can rapid infiltration basins (RIB) be amended to greater enhance the denitrification of nitrogen from effluent water. RIBs are areas of land (quite large in some cases, 5 acres or more) where effluent water is pumped back into the ground water. In that process, the physics behind it is that any nitrogen in the effluent water will be denitrified out. They want to know how we can amend this system so that we enhance that denitrification. The second component would be how does that system that removes nitrogen leaching compare with home lawns and spray fields? Which of these systems – spray fields, lawns or rapid infiltration basins – are the most effective at reducing nitrate leaching into the ground water?

Was there a greenhouse phase to this project?
TS: We had a greenhouse phase that was conducted in Fort Lauderdale that looked at a factorial design of many amendments – 64 columns and a manifold identical to the one we’re doing in the field. In the greenhouse we were looking at which of these amendments are most effective at reducing nitrate leaching. From the results of that greenhouse phase we selected the most effective and that’s what you see out at the Envirotron now.

Which amendments advanced from the greenhouse to field phase?
TS: What we’re dealing with is basically a bioreactor – which is a system designed to greatly enhance the microbial activities responsible for denitrification. How do we do that? We end up applying treatments that have large quantities of soluble carbon, which generally is the limiting factor in microbial growth. I’m not a microbiologist, but the literature indicates that if you add soluble carbon to certain systems you’ll see a reduction in nitrate leaching because it’s denitrifying. So the thought was let’s try this with sawdust, limestone, and biochar.

Rapid infiltration basins and lawns at the Envirotron 
We took those three amendments and then did a factorial. So we’re dealing with each individual one and then all the combinations of those three amendments and then the control which is sand. The amendments that were most effective were those containing sawdust. The amendments that did not contain sawdust had very little influence on reducing nitrate leaching. The treatments that we ended up pulling out into the field because we have such limited space are sawdust, sawdust/limestone, and sawdust/biochar. And then of course the control (sand) as well as st. augustine and bahia lawns.

How long do you anticipate this will be in the field?
TS: Well, it’s supposed to start now (summer) and it’s going to run for two years. It has to run 24 hours a day at a very very low flowrate (up to 10mL a minute) and it has to do that non-stop for two years. There are cycles when it’s flooding and cycles where it’s drying – floods for a week, dries for a week, non-stop 24 hours a day for two years straight. 

Tuesday, November 28, 2017

Florida Sinkholes Explained

By Eban Bean

Since Hurricane Irma, several sinkholes have developed around Alachua County and Florida, many in infiltration basins. An infiltration basin is sometimes also referred to as a dry retention pond or basin. You can find these in many residential and commercial areas where soils are sandy and the water table is not near the surface. Western Alachua County has hundreds of these.

Sinkholes are common in Florida, often forming after heavy rains. A popular video (see below) explains sinkhole formation, but there’s more to consider with development and stormwater management.

Karst Talk
Weak acids dissolve karst, CaCO3. Karst refers to topographic features where the subsurface is dissolved by surface or groundwater. This leaves large openings that allow water to move very quickly through the material. Karst is not unique to Florida and can be found in many parts of the US and around the world. Karst topography and sinkholes are naturally occurring.

Infiltrated rainfall leaches organic acids from surface that naturally dissolves Florida karst. Acid rain can accelerate this. Eventually, voids develop and overlying soil is not supported, collapsing at the surface. In well drained, undeveloped landscapes infiltration occurs across the entire area, uniformly except in low lying areas. When urbanized, runoff is conveyed from impervious areas commonly into dry infiltration basins. Several times more water is now infiltrating through the bottom of the basin, compared to before the area was developed. The acids in rainfall or from the landscape are focused in a much smaller area, accelerating dissolving CaCO3. Increased infiltration volumes also accelerate erosion of overlying soils as the karst void develops.

Sustainable Solutions
Sinkhole in Land O' Lakes, FL - Summer 2017 (image via NYT)
Sinkholes are often ‘fixed’ by filling them with concrete to stabilize the soil and geology below. Green infrastructure (GI) and low impact development (LID) distribute infiltration in developed landscape, using it more effectively. Examples of GI & LID: permeable pavement, bioretention, swales, cisterns, downspout disconnects, and infiltration trenches. Several local governments have incorporated LID practices into recent updates to stormwater programs. The water management districts are generally in support of it as well. The big hurdle is mainstreaming it into the engineering and design process. The first step in that direction is showing examples of these types of practices and projects where they not only perform well, but are cost effective, and easily maintained, compared to the conventional approach to land development.

Green infrastructure examples
We will be putting out a new series of EDIS documents and short videos that cover individual practices in the next few months. We are also working with developers to implement LID and green infrastructure into their projects, and evaluating the effectiveness of these practices. In the future we expect to offer continuing education for engineers and landscape architects on these subjects. UF/IFAS works with developers, government officials, and researchers on solutions for a more sustainable Florida future.

Tuesday, November 14, 2017

My Week with the Irrigation Industry: An E3 Report Back

By Justice Diamond

Experience, exposure and education are the three tenets of Irrigation Foundation’s E3 Learner Program. This is accomplished by inviting selected students to take part in a week of course work and networking during the annual Irrigation Show and Education Conference. 2017’s E3 Class included 28 students and 2 instructors from 17 states. IrriGator asked UF-ABE masters student Justice Diamond to report back on his E3 experience in Orlando, Florida.

E3 Learner Justice Diamond and industry reps 
My focus
The focus of my graduate work is to develop best management practices and deliver those to farms throughout the Suwannee and lower Suwannee basins in North Florida. What I’m working on specifically is to develop an app for irrigation scheduling for corn.
Suwanne River Basins (USGS)
My advisors Drs. Migliaccio and Dukes encouraged me to apply when they saw the opportunity arise and I went ahead and applied. The courses I selected for E3 were Landscape Water Management and Planning and Center Pivot Design. I’m really interested in Center Pivot technology and was especially looking forward to learning more about that.

The Big Week
My E3 experience was very positive. The highlight of the week for me was getting to know other people - having conversations about what they’re doing, the research they’re doing, and having conversations with people in the industry about how they perceive what the industry is going to look like in the future and what they want out of students. 
The least enjoyable part was how long classes were. The teachers were very good, but with an eight hour class there actually isn’t a lot of time to go see the exhibits and I think that part could be condensed. Nevertheless, having an in depth discussion with someone who lives and breathes center pivots I learned a whole lot more. In that sense it was very educational.

Sponsors like The Toro Company ensure the success of the E3 Program
Thank you to the Irrigation Foundation for the opportunity to participate in E3. Meeting people who are all about irrigation, it can only benefit me because that’s what I work with, too. I can only learn and grow from their experiences. My advice to eligible students in 2018: definitely apply! There’s nothing you can lose from the experience and you’ll only learn and meet people who will help you out in the long run.

Tuesday, October 31, 2017

Looking Ahead: Irrigation Show and Education Conference 2017

Next week irrigation industry professionals from all walks will descend on Orlando, FL, for Irrigation Show and Education Conference 2017. The largest irrigation-focused event of the calendar year, it is as advertised, part product expo (everything you can imagine and more) and part conference - academic presentations, training seminars and certification courses/exams. Best of all for our UF-ABE researchers specializing in irrigation, it’s only a 2 hour drive away.

Research Showcase
UF-ABE research will be featured in both the agriculture and landscape sessions of the Technical Program at Irrigation Show. PhD candidate Maria Zamora is presenting an overview of irrigation and nutrient best management practices in corn. Research associate Bernard Cardenas will discuss recent work pertaining to the EPA WaterSense pressure regulating spray sprinkler body specification

Dr. Michael Dukes will focus on finds from a multi-year Orange County (FL)-based smart irrigation technology study. And Dr. Kati Migliaccio is presenting on rainfall data resources for use in Florida.

E3 Learners
Once again this year I’ll be collaborating with the Irrigation Foundation on digital content. We hope to shine a light on the E3 Learners Program, which selects students from across the country to attend the Irrigation Show, complete coursework and network with established industry pros. This year’s Learner class is comprised of 30 students from 17 different states! Young people are the future of the industry, and the Irrigation Foundation is doing their best to welcome them into the fold.
I’ll also be live tweeting throughout show week. Catch me @IrriGatorUF and follow/tweet along with all the show goings-on at #IrrigationShow.

See you there?
If Irrigation Show 2017 can draw even a sliver of Florida’s sizable green industry/water sector it will be another successful event. If you’re reading this locally/regionally and you’re not sure about making the trek to Orlando this November, take Dr. Dukes' advice: “Just do it! Especially if you are in Florida - this is a great opportunity close to home to see the latest and greatest in irrigation products and tech! It won’t be back for at least several years.

Hear Bringing Water To Life Podcast's Irrigation Show episode:
Listen to "Episode 39 - 2017 Irrigation Show Preview" on Spreaker.

Tuesday, October 17, 2017

A WaterSmart Innovations 2017 Report Back

By Michael Dukes

WaterSmart Innovations is a can’t miss meeting for me because it is the single meeting of the many meetings I attend annually that focuses on water conservation. For me that means irrigation water conservation, but the meeting also covers indoor water conservation. It’s a good chance to let people know some of our latest results and to learn what types of research and implementation is happening with regard to irrigation water conservation in other areas of the country.
Given our proximity to the tragedy on the Las Vegas strip there was a somber feeling and mood to the beginning of formal sessions. We observed a moment of silence for respect to the victims. Doug Bennett, program chair, sent out a message regarding the tragedy. To sum it up he encouraged us to carry on in our small way to make the world a better place.
In the Audience
I chose sessions related to irrigation water-use; specifically about reducing peak demand through the use of smart controllers, education and or landscape modification. These are all topics we work on and I wanted to see the latest implementation from across the country. It’s noteworthy that smart controllers are no longer new and niche products. They are being implemented widely across the U.S. and many people are familiar at least in general what they are. Just a few years ago they were “new” and we had to explain what they were to people.

At the Podium
I was also tasked with presenting our work on the pressure regulating spray head (PRB) testing that was used by the EPA WaterSense program to develop their new spray sprinkler body specification. I feel it went well considering it was laden with technical details (I tried to trim as much as possible, but it’s a technical subject at the end of the day) and may have been boring to some non-tech folks. 
I got a number of technical questions and as a follow up met with some folks from California (CA). The CA Energy Commission is researching appliances for energy efficiency and water efficiency is directly related. In the near future (2019) they will have requirements for PRBs. I understand that non-PRBs will not be sold in CA after some transition date in the future. We may have the opportunity to do some more PRB testing in the lab to answer some of their questions. In fact a project proposal is currently being prepared!
Take Away
There were many good talks. Personally I was very interested in the talk by Joanna Endter-Wada about extension working with utilities in Utah to provide water consumption information to consumers. By understanding their detailed seasonal irrigation patterns and delivering targeted educational messages, they were able to significantly reduce over-irrigation. Excellent example of extension impacting stakeholders!

Tuesday, October 3, 2017

Researching Water Conservation Strategies with Dr. Mackenzie Boyer

This past summer Mackenzie Boyer successfully defended her PhD thesis and completed her work at UF-ABE. Dr. Boyer was the rare graduate student who returned to school following a stint in the professional world as a consulting engineer. As part of the Dukes research team she published the first journal article documenting water-savings in Florida-Friendly Landscape-certified (FFL) homes. Her work assessing effectiveness of outdoor watering restrictions in Florida was also novel terrain. On her most recent visit to Florida, Dr. Boyer agreed to speak with IrriGator about her research and more.

Dr. Mackenzie Boyer on defense day
What was the focus of your PhD research?
MB: The focus has been studying watering billing records to determine people’s irrigation habits in the Tampa Bay Water region (the SWFWMD area) trying to understand individual customer use for irrigation and then to also understand customer responses to irrigation conservation measures. So looking historically at how well the Florida-Friendly Landscaping Program has done, and how well water restrictions have done and then also projecting into the future how well could a utility do if they were to adopt different conservation strategies.

You came back to graduate school from the professional world. How do you feel this informed your perspective as a student?
MB: The first part of my career focused a lot more on the smaller details of water treatment and water system designs, but what was missing was more of the planning aspect – the big picture. I recognized what was missing in the work that I was doing with water and that’s one of the reasons why I went back to school. A great thing about this project is that we’re working directly with Tampa Bay Water and SWFWMD and the utilities. I feel like we’re impacting the supply side of water more so with our research now.

Dr. Boyer's area of focus in Florida
You recently relocated from Florida to Arizona. Do you get a sense that people relate to water differently out West?
MB: They do relate to it differently. Xeriscapes are much more popular there than FFL is here. But there are still a lot of homeowners that have turfgrass in the desert where you need to put 7 or 8 feet of water on your landscape during the course of the year. I think there is an appreciation of the amount of water that goes into a landscape in that alternative landscapes are accepted at a much larger scale. But for the people who choose to have turfgrass there isn’t the concern about water conservation or the right ways to irrigate your landscape.

The Dukes program tends to attract and develop really skilled water researchers. Do you have any insight as to why?
MB: This is a very important problem in residential water use. 50% of the potable water that goes to homes in the US ends up on people’s landscapes. This is a large area of potential conservation and the research that this group is doing can address an immediate need for better ways to conserve our potable water.

Dr. Mackenzie Boyer circa 2013

Currently you are prioritizing raising your family, but looking ahead to when you return to the work force how would you describe your ideal job?
MB: I hope to work in some area of academia or some area where I’m working directly with utilities. I’d really like to be helping inform utilities on their customers’ irrigation use and methods of conservation that would be applicable to their customers. The type of work that I did using water billing records, a lot of utilities are doing. There is a growing amount of data available to utilities and trying to help them to use that data to affect their water demand would be ideal.

There seems to be a lot of interesting work being done at Arizona State University and some of the cities like the city of Phoenix and the City of Scottsdale. Hopefully I can join some of their work and be able to contribute to it. 

Tuesday, September 26, 2017

Looking Ahead to WaterSmart Innovations 2017

Next week researchers, utility personnel and other water-use professionals converge on Las Vegas, NV, for 2017’s WaterSmart Innovations Conference (WSI). UF-ABE will be present in the form of two researchers from the Dukes group. Here is a look at what they will present at the event and other talks we are looking forward to learning more about.

UF’s contribution to this year’s conference focuses on irrigation technology. Research Associate Bernard Cardenas is presenting on the effectiveness of soil moisture sensor technology when used in residential irrigation systems on reclaimed water. Dr. Michael Dukes will discuss recent work on the pressure regulating spray head testing that was used by the EPA WaterSense Program to develop their new spray sprinkler body (SSB) specification. Did the high-nutrient content in reclaimed water interfere with soil moisture readings? Does SSB pressure regulating capacity vary at different flow rates? All will be revealed at WSI!

Sessions and More Sessions
WSI always offers a host of informative presentations. As Dr. Dukes said: “It’s a good chance to let people know some of our latest results and to learn what types of research and implementation is happening with regard to irrigation water conservation in other areas of the country.” Noteworthy talks this year range from water reuse to social media marketing to smart irrigation technology. Here are some sessions we are excited about:
  • Rainwater and Graywater Myth Busters
    Patrick Dickinson, Texas A&M AgriLife Research and Extension Center in Dallas
  • A Wild West Tale: Debunking the Myth That Conservation Increases Rate - Candice Rupprecht, Tucson Water
  • You Can’t Play Soccer in a Perennial Bed: The Case for Turf Sustainable Landscape -Paul Johnson, Utah State University for Water Efficient Landscaping
  • How We Got 10,000 Facebook Followers - Clint Wolfe, Texas A&M Agrilife Water University
  • WaterSense in Jeopardy: Saving the EPA Water Labeling Program - Mary Ann Dickson, Alliance for Water Use Efficiency
  • Water Conservation in Urban Communities: How the SNWA Does It - Jared Bilberry, Southern Nevada Water Authority 

WaterSmart Innovations always shares presentation pdf files at the end of conference week. Stay tuned for that and, whether you are attending or not, make sure to follow and contribute to conference goings-on on Twitter using #WSI2017.