Anusha Balangoda PhD

Dr. Balangoda's research is centered on harmful algal blooms (HABs), nutrient speciation and dynamics, and the origin, sources, and management of freshwater ecosystems. Her core expertise lies in phosphorus biogeochemistry and cyanobacterial bloom proliferation. She is particularly interested in the environmental factors controlling cyanobacterial blooms, sources and roles of nitrogen and phosphorus in eutrophication, cyanobacterial seasonal dynamics, nutrient limitation and stoichiometric ratios, and dynamics of toxin-producing HABs in aquatic ecosystems. She employs empirical field observations, stable nitrate isotope analysis, nutrient enrichment bioassay experiments, and statistical modeling across freshwater systems ranging from lakes and reservoirs to urban streams and rivers. Her work aims to inform recommendations and mitigation plans for nutrient enrichment and the development of HABs in freshwater ecosystems.

Research Projects

Role of Intermittent Artificial Destratification on Water Column Nutrient Concentration and Summer Cyanobacterial Blooms in Lakes and Reservoirs

Nutrient enrichment and excessive organic matter production have led to a suite of undesirable biogeochemical and ecological consequences, most prominently harmful algal blooms. Dr. Balangoda investigated the effects of intermittent artificial circulation — widely adopted as a restoration method to control summer cyanoHABs in eutrophic lakes and reservoirs. This collaborative effort was co-funded by NDSU, NDWRRI, and USGS.

Large-Scale Drinking Water Orthophosphate Addition on Urban Stream Chemistry, Algal Growth, and Nutrient Limitation

Despite the importance of phosphate addition as a corrosion control approach to protecting human health from lead exposure, knowledge gaps exist regarding the role of aging and leaking drinking water infrastructure on urban stream nutrient dynamics, nutrient limitation, and eutrophication potential. This project uses field sampling, onsite water quality monitoring, stable nitrate isotope analyses, algal bioassays, and eDNA techniques. Findings are applicable to other cities adding phosphate to drinking water. This collaborative project involves the Department of Civil and Environmental Engineering and the Department of Geology and Environmental Science at the University of Pittsburgh, in partnership with the Pittsburgh Water and Sewer Authority (PWSA), funded by a RAPID grant from the National Science Foundation (NSF) with contributions from Pittsburgh Water Collaboratory.

From Pipes to Streams: The Hidden Influence of Orthophosphate Additions on Urban Waterways (PLOS Water, 2025)

This study — published in PLOS Water in November 2025 — provides the first field-scale evidence that orthophosphate (PO4³⁻), widely added to drinking water to prevent lead pipe corrosion, can migrate beyond its intended domain and measurably alter the chemistry of connected urban streams. Working in collaboration with the Pittsburgh Water and Sewer Authority (PWSA), Dr. Balangoda and colleagues monitored five urban stream reaches before and after the city-wide initiation of orthophosphate-based corrosion control, capturing monthly stream chemistry across nutrients, dissolved metals, anions, and nitrate isotopes.

The study documented highly significant increases in streamwater phosphorus concentrations — total dissolved phosphorus rose by over 600% and total phosphorus by over 100% in the year following treatment. These increases coincided with elevated dissolved metal concentrations (copper, iron, manganese, and lead), implicating co-transport of corrosion byproducts through leaking pipe infrastructure as the likely pathway. Principal Component Analysis revealed that urban stream chemistry is shaped by a complex interplay of treated drinking water, pipe corrosion, mineral weathering, and wastewater inputs — with the orthophosphate signal emerging as a dominant driver following treatment.

Nutrient addition bioassays using the cyanobacterium Cylindrospermopsis sp. and the green alga Raphidocelis subcapitata confirmed that the elevated phosphorus concentrations significantly stimulated algal biomass, raising concerns about accelerated eutrophication in urban aquatic systems. The findings expose a critical and underrecognized pathway by which aging drinking water infrastructure contributes to nutrient enrichment in urban waterways — with implications for cities across the U.S. and beyond that are adding or considering adding phosphate to their drinking water supplies. The research was covered by The Allegheny Front, Eureka Alert, ASEE FIRST BELL, and WCP International.

Factors Driving Bloom Proliferation in the Ohio River: Nutrient Concentrations, Fluxes, and Hydrological Context

This collaborative effort began during the COVID-19 pandemic to understand factors driving cyanobacterial bloom proliferation in the Ohio River. In 2015 and 2019, two unprecedented Microcystis blooms occurred on the Ohio River, with microcystin toxin concentrations exceeding both EPA and WHO standards. Although HABs in lakes are frequently studied, HABs in rivers are less common and understudied. This project uses a regression-based approach to understand long-term nutrient concentrations and fluxes to the Ohio River.

Teaching Approach

Dr. Balangoda's teaching is grounded in the belief that students learn best when they are active participants in the construction of knowledge rather than passive recipients of information. She employs a range of evidence-based strategies tailored to courses of all sizes:

Inquiry-Based and Place-Based Learning

Students investigate real, locally relevant environmental problems — from Pittsburgh's urban waterways to regional ecosystem dynamics — using authentic field and laboratory methods. This place-based approach grounds abstract concepts in tangible, observable phenomena and connects coursework directly to ongoing research.

Hands-On Lab and Field Research Projects

Students conduct original research through structured lab investigations and field sampling exercises, developing technical skills in water quality analysis, nutrient bioassays, and environmental monitoring. These experiences mirror professional scientific practice and prepare students for research and careers in environmental science.

Cooperative Learning and Group Work

Collaborative projects and group activities are embedded throughout Dr. Balangoda's courses. Students work in teams to analyze data, design experiments, and present findings — building communication skills, scientific reasoning, and the ability to contribute constructively to a shared intellectual goal.

Pre-Reading and Social Annotation with Perusall

Dr. Balangoda uses Perusall, a collaborative social annotation platform, to engage students with primary literature and course readings before class. This approach promotes deeper preparation, encourages peer-to-peer dialogue around key concepts, and creates a more informed and participatory classroom. Her work using Perusall to foster inclusivity in large enrollment courses has been presented at national conferences including the Ecological Society of America Annual Meeting (2025) and the Perusall Exchange (2025).

Active Learning and Inclusive Course Design

Every course is intentionally designed to create an inclusive environment where students from all backgrounds can thrive. Dr. Balangoda uses active learning formats — think-pair-share activities, collaborative problem-solving, and discussion-based recitations — to encourage participation across all students. She holds Scholar-level teaching certification from the University of Pittsburgh and has received multiple awards for evidence-based course transformation. 

Courses Taught

• GEOL 0840: Environmental Science — 3 credits (large enrollment, 150 students)
• GEOL 1641: Ecosystem Ecology Lecture with Labs — 4 credits
• GEOL 1342: Environmental Issues (Writing Intensive) — 3 credits
• GEOL 1309: Limnology Lecture with Field and Lab Analyses — 3 credits
• GEOL 1516: Environmental Geochemistry Lecture with Labs — 4 credits
• GEOL 1045/2045: Statistics for Earth Science — 3 credits