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Development decision looms over Richmond Hill observatory lands

Karen Cilevitz, chair of the David Dunlap Observatory Defenders, in the David Dunlap Observatory Park in Richmond Hill, May 26, 2011.

Della Rollins/The Globe and Mail

The fight to save a swath of wooded conservation land surrounding a historic telescope observatory in Richmond Hill is nearing a close – but it remains unclear if the lone group fighting plans for a housing development on the property will prevail.

The Richmond Hill Naturalists have been involved in a hearing with the Ontario Municipal Board since the beginning of August, with the hopes of preserving an area known as the David Dunlap Observatory lands in its entirety.

The hearing is set to conclude on Sept. 10.

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An initial proposal from housing developer Corsica Development Inc. would have seen 833 houses built on the property, but it was rejected by Richmond Hill town council last year. The most recent settlement, which was agreed upon in April by the Town of Richmond Hill, the Toronto and Region Conservation Authority, the Regional Municipality of York and another group known as the David Dunlap Observatory Defenders, reduced the number to 530.

The proposed agreement would see the western portion of the property, about 60 per cent of the total acreage, gifted to the town. That property is where the historic telescope observatory and related buildings are located.

The David Dunlap Observatory property, which is located at 123 Hillsview Dr., consists of approximately 72 hectares of woodlands, wetlands and heritage plantations. Roughly three-quarters of the main property is currently designated as a cultural heritage landscape under the Ontario Heritage Act (which excludes a southern "panhandle" purchased by the town earlier this year).

However, Richmond Hill Naturalists president Marianne Yake says that any development on the property would not only be detrimental to the observatory lands, but surrounding neighbourhoods and cities as well.

The group filed a grievance with the Ontario Municipal Board after the April agreement was announced.

"Initially, I thought there should be some development," Ms. Yake said. "But as we did the research … we felt it should be left intact."

The group's primary concerns are the natural features of the observatory lands – specifically, the underground water resources, wetlands, and significant woodlands where about two dozen deer are estimated to currently live.

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Her group's fear is that removing wetlands and trees that typically absorb the water from an underground spring will make the surrounding neighbourhoods more prone to flooding, and affect streams and rivers in Richmond Hill, Thornhill and Toronto.

"If you're taking a green space that currently fulfills much of the natural sponge absorption of water," she explains, "[it] can create problems downstream."

However, both the town and Corsica say that these features can preserved if adequate drainage – such as a storm water pond – is installed, and lost trees replaced.

Other issues, such as how increased light pollution will affect the observatory's continued operation and the fate of the property's deer, have also been discussed.

The observatory lands were a gift to the University of Toronto by Jessie Donalda Dunlap in 1932 as a memorial to her astronomy enthusiast husband, David Alexander Dunlap.

Since 1935, the site has been home to the David Dunlap Observatory, the largest optical space telescope in Canada. In 1971, Canadian astronomer Dr. Tom Bolton famously used the telescope to confirm the existence of black holes.

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The land was sold to Corsica affiliate Metreus in 2008.

The David Dunlap Observatory Defenders – one of the groups that now supports Corsica's revised development plan – once hoped it could save the entire property from development, too.

However, Jason Cherniak, a lawyer representing the group, said in a statement in April that "it became clear that some portion would be indefensible against the OMB."

In other words, it was either save as much of the property as possible, says DDO Defenders chair Karen Cilevitz, or none at all.

"The gain is that these lands never belonged to the town," she said of the 99 acres acquired by the town (111 including the southern panhandle). "They were either in private ownership or belonged to the University of Toronto."

Editor's note: Karen Cilevitz's name was spelled incorrectly in an earlier version of this story.

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