The Grand Challengers Podcast Episode #62

Throwing your heart beyond the fence with treatment wetlands and NBS

Guest: Anacleto Rizzo

May 5th, 2026

Overview

What does a horror-game-loving Italian engineer have to do with cleaning your wastewater? More than you’d think… and the journey starts in a paddy rice field.

In Episode #62 of The Grand Challengers Podcast, host Peter Marcus Bach welcomes Dr Anacleto Rizzo — Partner at IRIDRA Srl in Florence, President of Global Wetland Technology, and one of Europe’s most active voices on nature-based solutions (NBS) for the water sector. They begin where two self-confessed geeks should: David Lynch films, Resident Evil vs Silent Hill, and the perils of playing first-person horror games next to a sleeping spouse.

From there, the conversation winds through Anacleto’s serendipitous journey into engineering, a randomly chosen civil degree at Politecnico di Torino that ended, unexpectedly, in a PhD on methane emissions from paddy rice fields. He explains why Italy’s Piedmont rice country is a methane hotspot (with a vivid biological analogy involving plant aerenchyma), and how a single review paper on treatment wetland modelling, read at the right moment, redirected his career toward nature-based wastewater treatment.

Treatment wetlands are the through-line of this episode: a quietly revolutionary technology with 30+ years of practice, capable of treating tens of thousands of population equivalent, yet still chronically misunderstood. Anacleto and Peter unpack what they actually are, surface flow vs subsurface flow, French Reed Beds, aerated wetlands, why a few “Wild West” early failures in Italy still haunt adoption decisions, and how IRIDRA evolved from a treatment-wetland specialist into a multidisciplinary NBS practice covering sponge cities, green walls and circular water loops.

The deeper thread is the academic-practitioner bridge. Like Bill Hunt’s perspective on America’s evolving stormwater management and Jon Hathaway’s “Swiss Army Knife” framing of green infrastructure among many other episodes on NBS, Anacleto argues that treatment wetlands matured because practitioners went out and monitored real, full-scale systems, generating the unglamorous “Q2/Q3 papers” that lab-scale studies could never produce. He shares why “throwing your heart beyond the fence”, a wonderful Italian idiom for calculated risk-taking, is the only way to escape the technological-readiness-level trap.

Flagship projects include the Gorla Maggiore water park in Lombardia (a multifunctional CSO treatment wetland featured in the FP7 OpenNESS ecosystem services project), the Orhei wastewater treatment plant in Moldova (20,000 population equivalent, among Europe’s largest), and ongoing Horizon Europe work in HYDROUSA, MULTISOURCE and CARDIMED. The episode closes with reflections on innovation, multidisciplinarity, two career-defining mentors (Luca Ridolfi and Fabio Masi), and a moving tribute to Anacleto’s late father.

Recommended for civil engineers, water professionals, NBS practitioners, urban planners, sustainability researchers, sponge-city designers and anyone curious about how nature does the dirty work better than concrete ever did.

Episode Teaser

A horror-game-loving Italian engineer, a PhD on rice paddy methane, and 30 years of treatment wetland practice — Episode #62 with Anacleto Rizzo (Partner at IRIDRA, President of Global Wetland Technology) is a masterclass in why nature-based solutions need practitioners who are brave enough to “throw their heart beyond the fence.” A deep dive into treatment wetlands, the academic-practitioner bridge, and the Italian projects shaping the future of urban water.

Biography

“…Be brave enough to implement innovation when you have then possibility…”

Dr Anacleto Rizzo is a Partner at IRIDRA Srl, the Florence-based engineering and consulting company specialising in nature-based solutions for the water sector, and the current President of Global Wetland Technology (GWT), an international consortium of leading treatment wetland companies operating across nine countries and three continents. A civil engineer trained at Politecnico di Torino (Bachelor’s 2008, Master’s in Hydraulic Engineering 2010), Anacleto holds a PhD (2013) from the Department of Environment, Land and Infrastructure Engineering on Modelling human-made wetlands for a sustainable development: investigation of paddy fields and constructed wetlands, supervised by Professor Luca Ridolfi, Professor Roberto Revelli and Dr Fulvio Boano. During his doctorate he completed a research stay at BOKU University Vienna with Professor Günter Langergraber, which marked his entry into the world of treatment wetlands, a field he has since helped shape at international level. He joined IRIDRA in 2015, became Partner in April 2018, and now leads research, development and design across the company’s portfolio of nature-based solutions.

At IRIDRA, Anacleto’s work bridges applied research and practical implementation across treatment wetlands, sustainable urban drainage systems (SuDS), green-blue infrastructure, sponge cities, ecosystem services and circular economy. Beyond his GWT presidency, he serves as Co-chair of the IWA Working Group on Nature-Based Solutions, Secretariat of the IWA Task Group on Nature-Based Solutions, and is a Management Committee member of the EU COST Actions on Circular Cities (CA17133) and Water4Reuse (CA23104, where he co-leads Working Group 5 on data and databases for water reuse). He is a co-author and co-editor of three foundational open-access IWA texts: Treatment Wetlands (Volume 7 of the Biological Wastewater Treatment series, 2017), Wetland Technology (2019, co-editor), and Nature-Based Solutions for Wastewater Treatment (2021, co-editor), sits on the Editorial Board of Science of the Total Environment, and has authored over 40 peer-reviewed papers (2,100+ Google Scholar citations, h-index 23). He has been a team member or in-house consultant on the Horizon 2020 / Horizon Europe / Interreg / LIFE / PRIMA projects HYDROUSA, MULTISOURCE, NICE, NAWAMED, PAVITR, AGREEMed, P2GreeN, AWARD, CARDIMED, SEACURE and FutureLakes, and has designed full-scale treatment wetland systems worldwide, including the Orhei plant in Moldova (20,000 PE), the Gorla Maggiore water park in Lombardia (a multifunctional CSO treatment wetland featured as a flagship case study in the FP7 OpenNESS ecosystem services project), and the Metropolitan Sponge City of Milan recovery-fund programme (26 of the 32 municipal interventions designed by IRIDRA).

Dr Anacleto Rizzo headshot — Partner at IRIDRA Srl Florence and President of Global Wetland Technology, civil environmental engineer specialising in treatment wetlands and nature-based solutions

Quick Summary & Highlights

  • Why paddy rice fields are a methane hotspot and how a PhD on agricultural greenhouse gas emissions led, by sheer serendipity, to a career in treatment wetlands
  • Treatment wetlands 101: surface vs subsurface flow, French Reed Beds, and why a technology that’s been working for 30+ years is still misunderstood at planning tables
  • The academic-practitioner bridge: why monitoring full-scale systems generates the evidence base that the technological-readiness-level framework will never capture from lab studies
  • Flagship projects: the Gorla Maggiore water park, the Orhei plant in Moldova (20,000 PE), and the Metropolitan Sponge City of Milan recovery-fund programme
  • “Snobs” vs “smarts”: IRIDRA’s playful typology for nature-based solutions that produce versus consume non-conventional water, plus reflections on innovation, multidisciplinarity and the Italian idiom of “throwing your heart beyond the fence”

Resources Related to the Episode

Key Research / Publications

EU & International Projects (Anacleto as team member or in-house consultant for IRIDRA)

Background / Context

Cultural / Fun References

Episode Chapters

(Chapters are embedded in the episode for quick access, click this to expand and view all chapters and time stamps)
  • 0:00 Intro
  • 1:59 Guest Intro, Cult Movies & Horror Games
  • 7:47 Why Civil Engineering?
  • 10:16 A PhD on “rice flatulence”
  • 14:48 Adding treatment wetlands to the mix
  • 19:06 A 101 on Treatment Wetlands
  • 37:17 The terminology discussion and IRIDRA
  • 51:42 IRIDRA’s Projects & Global Wetland Technology
  • 56:46 General receptivity of NbS in Italy
  • 1:03:08 Some exciting things Anacleto is embarking on
  • 1:07:15 Q&A Start
  • 1:07:26 What does innovation mean to you?
  • 1:08:30 Key event, book, person
  • 1:09:51 Time Management
  • 1:12:46 Favourite childhood memory
  • 1:13:45 Greatest challenge to date
  • 1:15:25 Advice for young professionals
  • 1:18:03 What would you most like to be remembered for?
  • 1:20:11 Where can people find you?
  • 1:20:58 Final message
  • 1:21:19 Outro

Connect with Anacleto Rizzo

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Credits