2025-049-E-County Mgr-Urban Sustainability Solutions-Green Infrastructure and Workforce Development Project

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2241 12. How many tons of greenhouse gas emissions will your project reduce/avoid each year? Please list any data sources used and show the steps of any calculations. Feel free to submit in a separate document if clearly labeled. * NOTE: the MDPI study used for these calculations and those in our 2023-24 OCCCA grant contained a calculation error which has been corrected in this 2024-25 OCCCA grant application. Because carbon-sequestration research to date has concentrated on urban canopies provided by trees, very few quantitative studies have been conducted regarding non-arboreal plants, many of which have substantial CO2-absorption capacities. We know that ferns, lilies, yucca, and other rain-garden plants reduce CO2 in their immediate vicinities by 10% or more (https://8billiontrees.com/trees/how-much- co2-does-a-tree-absorb/). In fact, Scientific American credits the small- leaved Azolla fern with cooling the entire Earth when it was overheated with greenhouse gases 55 million years ago: https://www.scientificamerican.com/article/can-the-fern-that-cooled-the- planet-do-it-again/. A 2022 study conducted by an international team of scientists (including one from NC State) showed that planting virgin ivy plants globally on bare urban walls and roofs could capture over 3.5 billion tons of CO2 annually (https://www.mdpi.com/1996- 1073/15/5/1683), amounting to 6.9% of global greenhouse gas emissions and rendering the Green-Walls-and-Roofs concept an applicable technology for decelerating global warming. The MDPI study referenced above calculates the average CO2 capture per ivy-covered house to be 1.001018 tons//year: https://www.newsnationnow.com/business/your-money/gas-costs- hundreds-more-for-average-american/). This number should approximate the amount of CO2 captured by one 3280 ft2 rain garden or vegetative riparian (stream-side) buffer (given that the average house has 1580 ft2 exterior walls + 1700 ft2 roof: https://sidingauthority.com/estimation-calculator/ and https://bmroofing.com/how-much-does-the-average-roof-replacement- cost/, respectively). We are applying for enough funding herein for 10 such-sized raingardens/riparian-buffers installations (1 project/group for 10 afterschool cohorts). As such, the installations put in the ground via direct use of this OCCCA funding should sequester as much as 10 tons of carbon capture per year. At the bare minimum, and because UrbanSS BMPs utilize native grasses, it is important to consider recent scientific studies demonstrating that one acre of native prairie grass can store up to 5 tons of carbon in its roots/soil per year (https://www.washingtonpost.com/climate- solutions/2020/08/19/climate-change-prairie/; see also https://grownative.org/learn/native-plants-store-carbon/ and https://climatechange.ucdavis.edu/climate/news/grasslands-more- reliable-carbon-sink-than-trees). One acre of water-absorbing vegetative stormwater bmp installations (rain gardens, riparian buffers, etc.) will, therefore, store at least this much; so, at the absolute minimum, the vegetative BMPs enabled by the OCCCA funding we request here (amounting to around 1 acre in total) will sequester a minimum of 5 tons of CO2 per year. As stated by Steven Apfelbaum in Every Child Can Help Fight Climate Change by Playing in the Dirt, “Scientific analyses show that recapturing atmospheric carbon into soil and plant communities is the easiest and least expensive method for mitigating climate change and that it provides many other economic, cultural, and ecological benefits. Restoring soils in currently farmed land can rein in 10 to 15 percent of the annual carbon emissions Americans create. Replanting native grasslands and restoring drained wetlands can reduce carbon emissions up to another 20 percent” (https://kidsgardening.org/soil-can-help-fight-climate-change-kids-need- to-get-dirty-and-learn-about-soil-2/). Finally, for sites where riparian buffers are useful, the teachers and students will plant site-dependent native trees. A mature live tree can Docusign Envelope ID: 7E7D300B-F83F-4917-A8A3-638B79C7D566