By Sharon Vanderslice

The latest controversy over the McLean development has to do with a tributary of Wellington Brook, a stream that originates on the hospital’s property and tumbles down the side of Belmont Hill before disappearing under Pleasant Street across from the supermarket.  There it joins the Wellington, travels through underground culverts, and reappears on the other side of Common Street near the Unitarian church. The brook continues behind the Armenian church and the public library, then dips underground again before flowing into Clay Pit Pond.

Three years ago, the Belmont Conservation Commission declared the portion of the brook that is on the McLean land to be “intermittent,” which means that it dries up periodically during periods of low rainfall.  A designation of “perennial,” meaning that it has an almost constant flow, would have put restrictions on nearby development, as mandated by the Rivers Protection Act.  The act requires that any new development be set back at least 200 feet from a perennial stream to avoid disrupting or polluting the stream’s natural flow.  In this case, anything that gets into the stream would end up in the Mystic River and eventually in Boston Harbor.

Already, pollution in this brook is a problem.  This past winter, it tested positive for high levels of E.coli, an indication that sewage is leaking into the water.  In February, Belmont resident Barbara Passero reported that it was polluted with heating oil.  McLean maintains that no more than 10 gallons were spilled, and thus no formal report had be filed with the town.  But as of last month, there were still large booms in the stream, put there to absorb leaking oil.  Incidents like this are one reason why the Rivers Protection Act was passed in August 1997. 

Setback Could Reduce Size of Development

In December of that year, in response to concerns raised at the time, McLean volunteered to keep development a hundred feet back from either edge of the stream.  A 200-foot setback, on the other hand, would likely mean a reduction in the size of its proposed senior housing facility.  This development is currently planned to hold 482 units.

On March 14, 2001 an abutter to the McLean property, Martha Eakin of Trapelo Road, asked the Conservation Commission to re-evaluate the status of the brook, which comes up for renewal every three years.  Although the stream was observed to be dry on least one day in July 1997, Eakin believes that this was an aberration, as the data were collected during an unusually dry summer.  Even perennial streams can dry up in a drought of sufficient duration, one in which precipitation is considerably below normal for four months or more.

To present Eakin’s case to the Conservation Commission, the Belmont Citizens Forum hired a professional hydrologist and wetlands scientist, Patrick Garner, to study the six-acre watershed and make recommendations.  Garner is a technical adviser to the Department of Environmental Protection on storm water issues and on questions having to do with intermittent and perennial streams.

Waverly Spring is Original Source

During his presentation in April, Garner showed maps of the McLean property dating as far back as 1893.  The maps show the source of the brook, which the Conservation Commission calls Junction Brook, to be a spring (labeled Waverly Spring) north of what is now Higginson House.  The surrounding wetlands were at some point covered over to create a tennis court and later paved for a parking lot.  “The spring itself,” Garner reported, “has been capped with a manhole.”

This does not mean that the water has disappeared, however.  A report from the McLean consultant Frank DiPietro says that before 1939, when the hospital was hooked up to the municipal water system, well water from the spot was diverted to make steam heat for the campus.  Garner believes that water from the spring is still flowing under the parking lot and emptying into the brook.  He recently asked permission to conduct a red-dye test in order to prove his assertion, but the hospital denied the request.

McLean maintains that the brook is primarily fed by storm water, and thus is more likely to flow intermittently.

De-Watering Operation Question

Questions have been raised about an existing de-watering operation on the property, a pumping system for drawing off ground water and funneling it into the storm drain system.  Garner said this could artificially decrease the flow in a brook that is perennial under natural conditions.  Stephen Kidder, a lawyer for McLean, has countered that the “de-watering at the Hospital has been approved by the DEP and the Environmental Protection Agency.”

Additional arguments presented to the Conservation Commission by both sides focused on how and where rainfall is measured, whether the stream has dug its own course or has been artificially channeled, and how much organic material still exists under the Higginson parking lot, which is due to be torn up when the R&D facility is built.

On May 15, the ConCom voted 4-1, with two members not voting, to designate the stream as “intermittent” once again.  Any appeal of this decision would be heard by the Massachusetts Department of Environmental Protection.

Sharon Vanderslice is a Town Meeting Member in Precinct 2.