Dr Pinar Balci – NYC water lead at WSP – offers her thoughts on how nature-based solutions are being developed in response to climate change.  

 

EA: Based on the experience of WSP, and working with your clients and other stakeholders in the water sector, how has the field of nature-based solutions (NbS) advanced in the past year or so?

PB: Nature-based solutions have advanced in light of the challenges many utilities are facing due to climate change: too much, too little and too dirty water. Some 90% of climate challenges are water related. Our communities flood because of cloudburst storms or storm surges and sea level rise; water pollutes because of heat and intense uses and discharges. NbS are at the center of climate adaptation, and provide cost-effective and equitable solutions to climate change challenges the water sector faces while providing co-benefits to our communities compared to the gray solutions. 

WSP has created a living breakwater – a billion oyster reefs to filter water, promote biodiversity and protect against storm surges in New York, which has endured an increasing number of flood-inducing storms. In Florida, we spearheaded the largest environmental restoration project in US history, a 6,300-acre water management project in the Everglades. 

 

EA: What are the stand-out NbS developments from your perspective? 

PB: In terms of urban applications, cloudburst management that relies on distributed green infrastructure solutions to mitigate flooding. Many communities have been facing increased intensity of rainfall events in a short duration of time (aka cloudburst), and these events are hitting the hardest among the underserved communities. Space and cost requiring large water storage facilities for flood mitigation is challenging in urban areas. Cloudburst management relies on the absorb, store and transfer principles, utilizing the green infrastructure to provide flood mitigation more cost-effectively. WSP is currently designing cloudburst interventions at two public housing complexes in NYC that are most vulnerable to stormwater flooding while keeping multi-purpose use and open space at the forefront to improve the lives of residents, mitigating flooding while providing overall resiliency for the surrounding neighborhood. 

 

EA: What are your tips for making the business case for nature integration linking to climate adaptation and resilience? And what are the key challenges? 

PB: Using the solution box to tackle more than one issue at a time. For example, NbS are critical for integrated planning. Many utilities face competing needs (climate change, meeting regulatory requirements, ageing infrastructure, workforce) and affordability challenges hence addressing wastewater, water and stormwater separately is no longer an option. NbS provide integration and opportunity to apply the one-water principles for utilities more cost-effectively and equitably for the communities they serve. Challenges are multi-folded, but significant ones are the lack of dedicated funding and maintenance. However, federal funding through SRF, FEMA, and CDBG are also available and used successfully in many places such as NYC, DC and other cities. 

 

EA: What barriers exist around the measurement, monitoring and reporting for NbS and biodiversity metrics? How can smart data tools and methods help to this end?   

PB: The tools to measure engineering performance, such as volume capture (i.e. storage volume) and pollutant reductions/loads and/or flood resiliency (stormwater runoff reduction) for watershed-based green infrastructure interventions, rely mostly on hydrologic and hydraulic (H&H) modeling coupled with water quality models in receiving waters. There are existing modeling tools available, however, in situ monitoring at asset level or within receiving waters where data is needed for validation and calibration of models are still challenging to collect for many utilities due to cost and level of effort required both spatially and temporarily. Partnerships with non-profit organizations and academia play a role in data collection and improvements for modeling accuracy. 

Another challenge for quantification of NbS benefits is how to quantify their “co-benefits” such as heat island reduction, improvements of ecosystem functions, or carbon sequestration benefits. These co-benefits are integral parts of the NbS toolbox both at watershed level and local neighborhood level, which require triple-bottom-line (TBL) analyses. The Water Research Foundation completed a research project in 2021 entitled “Economic framework and tools for quantifying and monetizing the triple bottom line benefits of green stormwater infrastructure,” which provides a systematic approach at the community, watershed, or neighborhood scale. 

Another example of smart data collection is what NYC DEP is doing to measure the flood mitigation benefits of distributed green infrastructure. NYC DEP is the largest utility in the US that has implemented more than 2,000 greened acres through the design and construction of GI to reduce combined sewer overflows. It has implemented robust H&H modeling coupled with asset-level research and monitoring to measure and quantify the stormwater volume and pollutant load reductions. To complement that, it is now implementing a flood sensor network working with local universities to measure the flood risk which also could be utilized to measure benefits of these distributed green infrastructure assets and will further the advancement of data collection and quantification of benefits. 

 

EA: What needs to be done to help close the so-called ‘nature funding gap’ between the climate and biodiversity crises, and create a more enabling environment in this UN decade of ecosystem regeneration? 

PB: Dedicated funding is a key for NbS implementation. The IIJA (Infrastructure Investment and Jobs Act) created opportunities for states, tribes and local governments in equitable, climate-smart infrastructure which NbS play an integral part in accomplishing these goals. More dedicated investments are needed to promote NbS, but also we need integrated policies and regulations to promote “One Water” where NbS are included as a key component. In 2019, the Water Infrastructure Improvement Act in the US was enacted, which officially recognizes the 2012 Integrated Planning Framework as a voluntary path that municipalities can take to maximize community benefits while meeting regulatory requirements. Although it’s a great start, more needs to be done to promote the framework and allow utilities to apply the “One Water Management” more comprehensively, including the Safe Drinking Water Act requirements and resiliency while keeping the NbS at the forefront. 

 

EA: What is the experience of utilizing biodiversity credits and offset opportunities?

PB: Utilizing biodiversity credits and offsets is crucial in combating environmental challenges and climate change impacts. However, our current experience reveals both successes and areas for improvement in maximizing the effectiveness of these mechanisms. Traditional carbon offset schemes have limitations, sometimes exacerbating issues. Yet, emerging solutions like biodiversity offsets offer promise, needing clear regulations and principles for integrity. We've seen monocultural forests result from poorly executed projects, signaling a need for robust conservation approaches. 

While private financing and regulatory pressures drive growth in ecosystem markets, success depends on holistic restoration and adherence to best practices. Prioritizing local impacts and ensuring equivalence to ecosystem loss are vital considerations. Moving forward, a nuanced approach is essential, recognizing ecosystem complexity and prioritizing lasting conservation outcomes. By combining regulatory measures, voluntary principles, and refining best practices, we can maximize the impact of biodiversity credits and offsets in protecting our planet's biodiversity.