The Landmarks Preservation Commission held a hearing yesterday on a plan by Columbia Grammar and Preparatory School to make rear-yard additions to its Upper West Side properties, a proposal that was approved, 26 to 8 with one abstention, January 5, 2010 by Community Board 7.

The plan would not only extend the rear-yards of six brownstones owned by the school at 20-30 West 94th Street but also add one story to three of them.

A spokesperson for Landmark West!, a civic organization concerned with the Upper West Side, told the commission that the school's plan "raises serious concerns" about the use of rear yards, noting that her organization recently commissioned a study of "backyard urban forests" from the City University of New York Institute for Sustainable Cities.

That study which was completed December 18, 2009, found that the city has 53,991 acres of privately-owned open space, or more than one-quarter of the total land area of New York City (304.8 sq. miles). The study said that the residential yard space is equivalent to sixty-two times the size of Central Park.

"Privately owned open spaces play a significant role in diverting stormwater from our aging water treatment system, saving the City water treatment costs while protecting the quality of our water. These spaces could capture as much as 1.4 billion gallons of water per inch of runoff - if the groundcover is permeable - since the more stormwater that seeps into the soil, the more water is diverted from the combined sewer system."

The study noted that during the summer, the city is on average 7 degrees Fahrenheit warmer than the surrounding areas and that "economic, environmental and public health effects of urban heat islands are far-reaching." "Higher temperatures can lead to heat stress in vulnerable populations and can also accelerate the photochemical reactions that form smog, which contributes to asthma and other respiratory problems."

Peter Samton of Gruzen Sampton, the architect for the school's plan, told the commission that the new spaces would be used by young students and would therefore mitigate noise problems on the street.

The Landmark West! Organization proposed that the school excavate about 16 feet underground for its expansion but, according to an article yesterday by Roland Li at observer.com Mr. Samton said that digging down into rock would be "very difficult." Landmark West, the article continued, "did, however, support the stripping of "garish red paint" from the facade in an attempt to preserve the row houses, and the installation of a rear stair system. Nadezhda Williams, a preservation associate at the Historic Districts Council, criticized the fire escapes, calling them 'West Side Story-esque.' But she warned against approving 'incremental additions' and future modifications that would ultimately lead to changes in the building that the LPC would not approve, had the modifications been proposed at once."

A January 13, 2010 article by Rochana Rapkins in the West Side Spirit noted that the Parks and Preservation Committee of Community Board 7 had issued a resolution describing the one-story rear-year extension as "relatively minimally intrusive to the character of the donut" - the area of common green space behind the school - "and to the views, light and air, and quality of life for the neighbors. At the meeting, Dr. Richard Soghoian, the school's headmaster, detailed the revisions, which included enclosing the air handler that produces a humming sound audible to nearby houses."