Category: Statewide

Water quality in Alleman Creek, a small watershed in Iowa,
will be monitored through stream nitrate sampling and streamflow monitoring. Nearly all
subsurface drainage tile outlets in this watershed were treated with an edge-of-field
nitrogen reduction practice (saturated buffer or denitrifying bioreactor) as part of the first
Polk County Batch and Build Project. This project will assess the effectiveness of these
edge-of-field practices at scale by quantifying the reduction in nitrogen mass leaving the
watershed. This watershed assessment will be contextualized with nitrate mass reduction
monitoring of three individual saturated buffers in the watershed. This research will
provide valuable empirical data on the effectiveness of edge-of-field water quality
practices at a larger scale as widespread implementation of these practices accelerates to
meet water quality goals.

Floods impact 2.2 billion people globally, and their occurrence displays an alarming increase
compared to other natural disasters. The State of Iowa follows this ascending trend, with flood-
presidential disaster declarations occurring almost every other year for the last 30 years. The
ever-growing flood threats continue to be tackled with piece-meal, sectoral mitigation
approaches that are trickled down to communities through top-down, limited-efficiency solutions
that disproportionally affect the socially vulnerable populations in rural and urban communities.
While considerable scientific and technological progress is increasingly available for many flood
mitigation efforts, their on-the-ground impacts are impeded, among other causes, by the limited
availability of tools to rapidly turn the expanding data into accessible and actionable knowledge
for flood mitigation. Changing the current situation requires a “system of systems” (SoS)
approach whereby the underlying hydrologic processes leading to floods are closely linked with
the watershed-level socio-economic functions through efficient collaboration tools to ensure
community involvement in the co-production of the mitigation plans with attention to socio-
environmental justice principles. Currently, there is no unified vision on the architecture,
components, and technologies for a generic flood mitigation and resilience support system.
The aim of the proposed research is to develop a prototype web-based mitigation platform,
Flood Resilience Support System (FloodRSS), for participatory community action where the
multi-disciplinary legacy datasets and incoming data streams are organized, stored, and analyzed
as a “big-data” case driven by emerging concepts in flood vulnerability and resilience. Our
proposal responds to the priority on “water related hazard and society” by linking flood
underlying hydrologic processes with socio-economic aspects within a generic and modular
cyberinfrastructure that can be iteratively enhanced with new developments as they occur.

Optical brighteners—or fluorescent whitening compounds (FWCs)—absorb light
in the ultraviolet and violet region of the electromagnetic spectrum, and reemit light by a process
known as fluorescence in a lower-energy region of the spectrum, namely in the blue region
(typically 420-470 nm). These additives are often used to enhance the appearance of the coloring
of fabrics and papers, causing a “whitening” effect; they make intrinsically yellow or orange
materials look less so, by compensating the deficit in blue and purple light reflected by the material,
with the blue and purple optical emission of the fluorophore [1-9]. Because these are synthetic
compounds and, consequently, not naturally occurring, they make excellent markers for detecting
leakage of wastewater into surface water as they are introduced into sewage from the detergents
used in clothes washing. We propose to characterize commercially available optical brighteners
that are used predominantly in laundry detergents to determine the uniqueness of their spectral
signatures and to ensure that there is no spectral overlap with spectral signatures from other waste
or from naturally occurring substances. We also propose to determine the lifetimes of the optical
brighteners in the presence of oxygen, light, microbes, and surface water as such environments
may contribute to their partial decomposition, rendering them potentially useless as analytical
probes yet still deleterious from a public health perspective. Funding for this proposal will, in
addition to ensuring the outcomes noted above, also continue the training of promising
undergraduate students, enable the submission of a larger federally-funded grant proposal, and
potentially permit the patenting and licensing of new detection technology (with which we have
experience, as noted on our vita and as indicated by our RD100 award).

Per- and Polyfluoroalkyl Substances (PFAS) are a class of over 6,000 persistent,
bioaccumulative, mobile, and toxic environmental contaminants that are ubiquitous in
wastewater and stormwater. PFAS exposure is linked to adverse human health outcomes and
lethal and sublethal toxicity in aquatic species. PFAS discharges in wastewater effluent draw
increasing scrutiny from states, including Iowa, and federal regulatory rule making is underway.
The best-studied and most frequently regulated PFAS are perfluoroalkyl acids (PFAAs). PFAAs
are also the terminal transformation products of many precursor PFAS with more complex head
groups. Wastewater treatment processes can transform many precursor species into PFAAs;
however, precursor species are less likely to be researched, monitored, or regulated than their
terminal transformation products.
We propose to investigate whether shorter hydraulic retention times during wastewater treatment
will result in less precursor transformation and therefore a greater discharge of PFAS which are
“invisible” to standard measurement protocols. Proper accounting of often-unmeasured precursor
PFAS—which may contribute to aquatic toxicity and can transform into terminal PFAAs in the
environment—will provide a more comprehensive understanding of PFAS discharge to
environmental waters from stormwater and wastewater. This improved understanding will enable
more informed treatment design and the establishment of effective and equitable regulations.

Climate change and urbanization are increasing the influence of municipal wastewater effluent on
receiving waters, making wastewater effluent-dominated streams common worldwide, including
in temperate regions. This phenomenon increases loading of contaminants of emerging concern
(CECs) including pharmaceuticals, personal care products, pesticides, and industrial chemicals
from wastewater treatment plants (WWTPs) to drinking water supplies (i.e., de facto reuse) and
ecological systems. Treated effluent from WWTPs releases CEC mixtures that vary
spatiotemporally, which generate complex exposure conditions for biota and potential for
deleterious interactive effects (e.g., drug-drug interactions). When individual CECs present in
mixtures are removed from the aqueous phase via sorption or degrade from the stream at different
rates (i.e., differential attenuation), exposure conditions for biota change. Attenuation rates of
CECs we measured in the field are much greater than those in batch degradation tests—suggesting
other relevant stream processes. Currently, we do not fully understand the role of groundwater-
surface water exchange on complex mixture evolution. There is a critical need to evaluate the role
of groundwater-surface water exchange as a driver of complex mixture evolution using next-
generation high-resolution non-target analytical approaches to quantify CEC spatiotemporal
dynamics.

The frequency of catastrophic flood events, amplified by climate change has increased
substantially in US Midwest (Neri et al., 2019; Reed et al., 2020). Flooding causes major
economic and social damage in the region. Because community vulnerabilities increase flood
impacts, vulnerability reduction is a crucial part of flood risk management. Many household
flood recovery projects often fail to address pre-existing community vulnerability, and in many
places the measurement of such reduction (if any) is difficult to identify.
The objective of the project is to determine how flood recovery measures facilitate the reduction
of unmet needs in a flood affected community. These unmet needs can be social, physical, health
or economic. The case study is based on two research questions: RQ1) What are the unmet social
needs of the flood exposed community? and RQ2) To what extent do flood mitigation measures
address unmet social needs? The study area is the City of Dubuque, which provided data
required for this project

The US Cornbelt is a leading global producer of intensively managed, row-crop corn and
soybeans – yet, the agricultural production of these commodities is often linked to challenges
associated with nonpoint source nutrient pollution that negatively impacts water quality and
highly altered hydrology that negatively impacts surface water discharge. Excess nitrogen and
phosphorus in surface water can have regional and local impacts on aquatic ecosystems,
recreational opportunities, livelihoods, and human health. Altered hydrology can lead to excess
discharge, resulting in extreme flood events. While these challenges affect many downstream
regional and local communities, underrepresented, underserved communities and communities of
color are often disproportionately impacted by these negative environmental externalities.
Floodplain management offers a unique opportunity to address challenges related to water
quality and water quantity to reduce downstream impacts. Floodplain forests represent a
potentially powerful water quality and quantity conservation practice, as rigid upright stems and
associated downed woody material and understory vegetation act to reduce flood flow velocities
and encourage water retention and infiltration. Deposition of sediment and associated
phosphorus are associated with reduced flood velocities, and deposition acts to transfer these
potential pollutants into long-term floodplain storage. Often overlooked is the ability of
floodplain forests to address riverine nitrogen loading. Through a combination of floodwater
retention, raised water tables, and sediment and organic matter deposition, floodplain forests
create zones of nitrate removal by encouraging processes such as denitrification. In addition to
larger water retention sites often associated with woody floodplain vegetation (e.g., oxbows),
individual trees and downed woody material provide abundant water retention microsites
through tree windthrow (e.g., pit and mound microtopography) and localized scour. Although
floodplain forests represent potentially significant nitrate sinks, research that quantifies nitrogen
removal within these areas is rare – especially in the agricultural Midwest. In addition, studies
that seek to link water quality and quantity impact with current forest species composition,
structure, and condition, and provide management recommendations to maximize water quality
and quantity return, are exceptionally rare.
The primary objectives of this project are to: 1.) estimate riverine nitrogen removal performance
of individual floodplain forest sites along major Iowa rivers, 2.) combine floodplain forest water
quality and quantity data with forest stand inventory to estimate watershed-scale impacts of
floodplain forests, and 4.) increase awareness and value of floodplain forest systems within
impacted, underserved downstream communities. To meet these objectives, we will employ a
combination of in-field monitoring and inventory, hydraulic floodplain modeling, a conservation
planning tool, and extension efforts. The results and outcomes from this project will be used to
create floodplain forest management recommendations, and maximize water quality (i.e.,
nitrogen) and flood mitigation returns for underserved downstream communities. Field data will
also be coupled with GIS-based modeling used by co-PI Zimmerman to quantify landscape-level
outcomes associated with floodplain forest management and key opportunities to maximize
restoration benefits. Associated extension programming seeks to increase awareness of
floodplain forest value to underserved audiences, and sustain management through promotion of
natural resource careers (e.g., forestry) within underserved downstream communities.