Item 27 - Appeal Application Nos. 2020-03 and 2020-04 - Central Pointe Mixed-Use Development

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Recent advances in structural glass engineering have contributed to a proliferation of glass windows on building facades. This proliferation is readily observable in newer buildings and in recent project planning documents, and it is represented by a worldwide 20% increase in glass manufacturing for building construction since 2016. Glass markets in the USA experienced 5% growth inboth 2011 and 2016, and was forecast to grow 2.3% per year since 2016 (TMCapital 2019). Increasing window to wall ratios and glass facades have become popular for multiple reasons, including a growing demand for `daylighting.' Glass is also a prominant feature of the proposed project, according to depictions of the buildings in the Staff Report. I estimated >70% of fagades could be composed of glass, including glass railings and glass walls. The depictions in the Staff Report include additional contributing collision hazards such as large transparent glass panels, interior lighting, nearby trees, and entrapment spaces interior to the building structures. Entrapment spaces would include `The Social,' `The Hangout,' `Outdoor Escape,' `Fireside,' `The Dinner Party,' `The Backyard,' `Garden Lounge,' `Public Plaza,' and `Entertainment Garden.' Birds entering these species grow increasingly desperate to get out, flying back and forth until colliding with a perceived escape that happens to be a glass panel. City of Santa Ana (2007, 2018) did not address the issue of bird -window collisions. The only window issue addressed was potential glare, to which the 2007 EIR specified on page i-5, "Proposed new structures shall be designed to maximize the use of textured or other nonreflective exterior surfaces and non -reflective glass." The only mitigation measures formulated to minimize bird impacts included preconstruction surveys for nesting birds, timing of tree removals to avoid the nesting season, and careful use of construction vehicles (MM-OZ 4.3-1). No measures were proposed to minize bird - window collision mortality. Glass -facades of buildings intercept and kill many birds, but these facades are differentially hazardous to birds based on spatial extent, contiguity, orientation, and other factors. At Washington State University, Johnson and Hudson (1976) found 266 bird fatalities of 41 species within 73 months of monitoring of a three-story glass walkway (no fatality adjustments attempted). Prior to marking the windows to warn birds of the collision hazard, the collision rate was 84.7 per year. At that rate, and not attempting to adjust the fatality estimate for the proportion of fatalities not found, 4,235 birds were likely killed over the 50 years since the start of their study, and that's at a relatively small building fagade (Figure 1). Accounting for the proportion of fatalities not found, the number of birds killed by this walkway over the last 50 years would have been about 12,705. And this is just for one 3-story, glass -sided walkway between two college campus buildings. 5