Using an Informational Design Approach for Environmental Project Planning and Restoration Management Monitoring under Climate Change

Richard Koehler

This research demonstrates novel ways to increase the understanding of the hydrologic regime, critical when designing and monitoring environmental and restoration projects. By using informational design concepts and a geo-temporal information system (GtIS), the following three data visualization and analysis techniques are possible.

1. The raster hydrograph. This dual time scale graph simultaneously displays daily, weekly, monthly, seasonal, annual and interannual flow patterns on a single plot, helping to identify climate change signatures. 
    
2. The enhanced flow duration curve (eFDC). The traditional FDC, the basis of TMDL monitoring efforts, has no chronological order information, limiting the ability to identify climate change within the streamflow record. The eFDC solves this timing issue by adding a dQ/dt point cloud around the traditional FDC. This results in new ways to visualize and analyze changes in flow patterns between comparison periods or generated scenario flows.
    
3. The dQ/dt matrix. An extension of the eFDC, this matrix displays and quantifies *all* hydrologic conditions within the observed or generated flow record. Data self-sorts within the matrix, showing regions of increasing flow (dQ/dt > 0), steady flow (dQ/dt = 0), and decreasing flow (dQ/dt < 0). The number and degree of discharge conditions are detailed, allowing for a Markov chain-like approach to summarize streamflow changes.

Other benefits include more efficient, higher resolution model calibrations and sensitivity analyses, greater plot customization, and improved communication of results to a wider audience.

Urban Flood Risk Management Under Climate Change

Yogesh Bhattarai; Amisha Bhandari; Rocky Talchabhadel; Sanjib Sharma

Urban areas increasingly face a wide range of stormwater management challenges, including clogging, maintenance requirements, and in particular insufficient drainage capacity during extreme rain events.These challenges are further exacerbated by rapid urbanization, aging infrastructure, and intensifying rainfall extremities driven by climate change. Traditional gray infrastructure alone often lacks the flexibility and capacity needed to manage these evolving risks. Nature-based solutions can offer a sustainable and adaptive approach by leveraging natural processes to reduce runoff, improve water quality, and enhance urban resilience. This study aims to quantify the value of integrating nature-based solutions (NbS) with engineered gray infrastructure to achieve sustainable stormwater management. We look into high-resolution geospatial datasets and combine them with physically-based hydrodynamic modeling, and finally explore likely future projections under several climatic and socioeconomic conditions to evaluate robust and adaptive risk management strategies across urban environments. Our analysis shows that adaptive integration of green and gray infrastructure can significantly reduce flood risk while improving system flexibility under uncertainty. NbS such as green roofs, bioswales, and permeable surfaces can complement traditional infrastructure by attenuating peak flows, enhancing infiltration, and providing co-benefits related to ecosystem services and urban resilience. The results highlight that strategically combining NbS with gray systems offers cost-effective and sustainable pathways for climate-resilient infrastructure development. This integrated approach supports long-term urban resilience by improving flood mitigation performance under extreme events while addressing future climate and development pressures.

Minimum Duration of Accumulation (MDoA): Improved Quantification for Intensity Distributions of Extreme Rainfall in Minnesota

Andy Erickson; Noah Gallagher; John Gulliver

Flood hazard modeling is important for many communities around the world, and urban flood risk is an area of increasing concern. Engineers often use combined hydrologic and hydraulic (H&H) models to simulate the impact of rainfall on their urban watersheds, identify flood risks, and implement stormwater control measures based on these model results. Many guidance documents and practitioners default to a “worst case” (Watt and Marsalek, 2012) when selecting the temporal distribution of rainfall. Hyetograph selection is particularly important for urban watersheds that are highly impervious and often have short times of concentration which makes the runoff response more sensitive to peak precipitation rates. This presentation proposes an alternative to commonly-used design storm distributions like nested distributions or Huff-style curves. We demonstrate that nested distributions are more intense than real rainfall distributions while Huff-style curves can underestimate runoff response. Instead, the Minimum Duration of Accumulation (MDoA) metric is a new approach to quantify intensity. A new family of hyetographs were created using MDoA to reflect the range of intensities observed in real precipitation events and is linked directly to risk of occurrence. These new curves are shown to produce runoff responses equivalent to varying percentiles of real storms for a range of soil types. Specifically, we propose using the MDoA derived curves in applications like ensemble modeling, where intensity and storm depth can be treated as distinct variables and identifying which combinations of intensity and depth cause failure conditions which could enable watershed managers to better understand system level risks.

A Planetary Boundary–Informed Distance-to-Target Framework for Evaluating Environmental Trade-Offs in Water Reclamation Systems

Mengshan Lee; Chichi Huang; Zih-Ee Lin; Huan-Yu Shiu

Advancing sustainable water and watershed management requires life cycle assessment (LCA) frameworks that not only quantify environmental burdens but also situate them with respect to ecological limits. This study develops Planetary Boundary (PB)–informed weighting factors (WFs) using a distance-to-target (DTT) approach and applies them to wastewater reclamation systems. The DTT method employs normalized impact references for different baseline and target years, generating three WF sets—WF90-00, WF90-95, and WF95-00—based on 1990/1995 reference years and 1995/2000 target years. With a functional unit of 1 m³ of product water, application of the PB-informed WFs generally reduces aggregated impact scores, reflecting the lower weighting magnitudes assigned to most impact categories. In WF90-00 and WF95-00, terrestrial ecotoxicity (TEP) exhibits the highest relative importance. These results indicate that TEP and freshwater aquatic ecotoxicity (FAEP) should be prioritized as key pressure pathways for targeted impact mitigation. When the framework is applied to wastewater reclamation systems, electricity use remains the principal hotspot, contributing a large share of impacts under grid-connected operation. Integration of renewable electricity substantially attenuates impacts, with wind power reducing contributions from 25% to 18% and solar power from 72% to 61%. Variations among scenarios are largely driven by the WFs for TEP and FAEP, while FAEP consistently remains the dominant contributor. Overall, this study provides a more rigorous, goal-oriented, and policy-relevant LCA framework to support climate-resilient and environmentally responsible regional water and watershed planning.