Staff

 Heather Hulton VanTassel, PhD
​Executive Director
​Interim waterkeeper

Heather Hulton VanTassel is an environmental conservationist passionate about nature-based solutions that lead to the sustainability of our planet and equality for all. Heather’s passion began in a small rural community in Western Pennsylvania and flourished as a first-generation college student at Carlow University majoring in Biology. Heather went on to earn her doctorate degree in Evolution, Ecology, and Organismal Biology at The University in California, Riverside (UCR). Heather has held positions at UCR’s Center for Conservation Biology as a Research Specialist, Audubon South Carolina as a Program Manager of Sustainable Solutions, The Nature Conservancy in South Carolina as the State Conservation Coordinator, and at The Carnegie Museum of Natural History as the Assistant Director of Science and Research. Heather has had formal training and certification as a Master Naturalist in South Carolina’s Lowcountry, Project Management Professional, Wetland Delineator, and Diversity, Equity, and Inclusion in the Workplace practitioner.  Heather has a strong passion for both the environment and equity and believes that working towards sustainability also requires an equal effort towards social environmental justice. In her free time, Heather enjoys hiking, spending time with her friends, family and pets, and (of course) recreating on our Three Rivers! 

Board of Directors
April 2021

Lisa Werder Brown
President

Lisa Werder Brown is the Executive Director of Watersheds of South Pittsburgh, formerly the Saw Mill Run and Streets Run Watershed Associations. She works closely with watershed communities, local governments, academic, and nonprofit partners to identify the issues and explore opportunities for storm water mitigation in the Pittsburgh region. Lisa is a graduate of Chatham University with a BS in biology and holds a Certificate in Nonprofit Executive Management from Georgetown University. She has served on the Board of Directors of Three Rivers Waterkeeper since June 2012 and is currently the Board President. Lisa also serves on the strategic working group for the South Western PA Water Network and is a member of the ALCOSAN Municipal Advisory Committee.   ​

Sarah Quesen, PhD, MPH
Vice-President

Sarah Quesen, PhD, MPH, is a senior research scientist with Pearson and an visiting lecturer in statistics at the University of Pittsburgh. Sarah is an avid open water swimmer, and she provides information on safety and river conditions throughout the summer season for local swimmers. Sarah is Vice President of the Western Pennsylvania Bicycle Club, the longest-running cycling club in the region. Sarah joined the Three Rivers Waterkeeper in April 2019, and currently serves as Vice President.  ​

Ben Mack
tReasurer

Ben Mack has spent his entire career in the environmental sector. He began his career as an Americorps VISTA volunteer with Friends of the Cheat, a watershed group in West Virginia. Ben also served as a Research Associate at the West Virginia Water Research Institute, where he designed and implemented water treatment projects for the remediation of acid mine drainage. He also served as an Environmental for the State of Delaware, where he managed long-term environmental cleanups on polluted sites. He is currently an environmental consultant with Tetra Tech where he works on a variety of environmental projects. Ben has a Master of Science in Plant and Soil Science and a dual Bachelor of Science in Agronomy and Environmental Protection, both from West Virginia University. In his spare time, he enjoys spending time with his family and being outside.

Rebecca Kiernan
SECRETARY

Rebecca Kiernan is a Principal Resilience Planner with the City of Pittsburgh, focusing on building social, ecological, economic, and physical resilience to city-wide shocks and stresses. Her work includes developing and implementing initiatives such as the ONEPGH Preliminary Resilience Assessment, Resilience Strategy and Investment Prospectus; the Pittsburgh Equity Indicators Reports; and aligning the City’s work with the UN Sustainable Development Goals. She also supports the City’s Climate Action Plan with a focus on transportation electrification, zero waste, and urban ecosystems initiatives. Rebecca was previously Sustainability Coordinator for the Township of Moon, worked in coastal livelihoods restoration in Indonesia, and has 7 years of experience in education and facilitation. She holds a BA in English and Education from SUNY Geneseo, and an MS in Public Policy and Management with a focus on Environmental Policy from Carnegie Mellon University. She serves on the City’s Shade Tree Commission and ALCOSAN’s Municipal Advisory Committee. Rebecca enjoys long road trips, growing stuff, and kitchen projects.

Josh Eisenfield
BOARD MEMBER

Josh is the Corporate Accountability Communications Campaigner at Earthworks, working to hold the oil and gas industry publicly accountable for their methane pollution. Josh began his career as a documentary filmmaker, traveling around the world making films about social justice while also working as a producer at a nationally recognized advertising agency. Outside of work, Josh volunteers his time as one of two PA Steering Committee members of the People Over Petro Coalition and as a member of the Fineview Citizens Council and the Green Party of Allegheny County.

Sean Brady
BOARD MEMBER

Sean is the Executive Director of Hollow Oak Land Trust, a conservation organization that protects and connects greenspace in the Pittsburgh International Airport Corridor. With a BA in Biology from Allegheny College and an MA in Professional Writing from Carnegie Mellon University, Sean helped build Venture Outdoors as a regional leader in outdoor recreation from its inception in 2001 to 2010. He also served as Development Director for Riverlife, supporting sustainable riverfront development in downtown Pittsburgh. Currently, Sean manages the six conservation areas owned by Hollow Oak Land Trust and works with municipalities and private landowners to develop greenways in the airport corridor.

Tim Fitchett
bOARD mEMBER

Tim Fitchett is a staff attorney and resident director at Fair Shake Environmental Legal Services, a non-profit environmental law firm based out of Pittsburgh, PA and Akron, OH. Tim is also on the Board for Calliope House, an organization devoted to promoting folk music in Pittsburgh and the surrounding area. Tim joined Three Rivers Waterkeeper in December of 2020 and is excited to help our rivers flourish. 

Kimberly Refosco
BOARD MEMBER

Kimberly Refosco is an educator and leader in both the classroom and the outdoors.  After studying Political Science and Spanish at the University of Pittsburgh, Kim earned her M.S. in Education from Franciscan University.  She currently teaches Spanish and English as a Second Language.  In addition to teaching, Kim is a consultant in diversity, equity, and inclusion, leading organizations to implement change and strive for justice.  In spare time, you can find Kim fishing, reading, and spending time with her two teenagers.  

Kate Zidar
bOARD mEMBER

Kate Zidar is a PhD student at the University of Pittsburgh and a native Pittsburgher. At Pitt, she is a member of the Elliott Lab, where she participates in research that examines the impact of human activities on aquatic and terrestrial ecosystems. Previously, she worked as an Environmental Planner with a professional focus on green infrastructure, resilience and communications.  Kate earned a M.S. at the Pratt Institute in City and Regional Planning where she also taught for seven years.  She was a founding member of the Stormwater Infrastructure Matters (S.W.I.M.) Coalition, a policy think tank that figured centrally in establishing Green Infrastructure as a mainstream practice in New York City. She also began the North Brooklyn Compost Project, one of the many community garden-based efforts that ultimately “made the road by walking”, preceding city-wide collection of organic waste in NYC.  Today, Kate’s research explores the underlying biogeochemical processes of Green Infrastructure.

Joshua Powell
bOARD mEMBER

Kelsey McNaul
BOARD MEMBER

Kelsey McNaul is a regional organizer for The Climate Reality Project, working to build coalitions in the Ohio River Valley to stop the petrochemical buildout of the region. Growing up in Lancaster PA, Kelsey has always fostered a passion for environmentalism and social justice. Her activist spirit led her to obtain a dual degree in Environmental Studies and Sociology at Washington College in Maryland, where she coordinated grassroots environmental campaigns on campus. Upon graduation Kelsey furthered her activism work as a field organizer for the Fund for the Public Interest. An avid traveler, her time hiking, kayaking, snorkeling, and scuba diving domestically and around the world have only solidified her love of the environment. In her free time, Kelsey enjoys exploring natural and urban areas, snuggling with her dog Lila Rae, and dancing like no one is watching.

Emily Constantine Mercurio,
​PhD, PG
Board Member

Joshua Powell is an engineer at Broadcom, Inc., a designer, and supplier of semiconductors and infrastructure software products. Joshua has spent the past 15 years working closely with non-profit organizations focused on environmental conservation and restoration by building award-winning software. Joshua joined Three Rivers Waterkeeper in December 2020. In his free time, he enjoys gardening and spending time outdoors with his family.

Emily Constantine Mercurio is  a big thinker and a lifelong learner. She is an experienced geoscientist and an expert in mapping, field geology, GIS, remote sensing, and geospatial technology. As co-founder and CEO of CivicMapper, Emily draws upon more than 20 years of experience as a leader in map-based technology projects. Her current work is focused on creating spatially-enabled applications that empower decision making on the front lines of climate change, infrastructure, and social equity. Emily is a licensed professional geologist in the state of Pennsylvania. In addition to service on the Three Rivers Waterkeeper board, she also sits on the board of the Pennsylvania State University Graduates of Earth and Mineral Science. She enjoys gardening, visiting hot springs, making art, and spending time on the water with family and friends.

Rachel Cook
BOARD MEMBER

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