My wife and I attended the hearing for the Jones Estate re-zoning application on Sept. 10. We live in the community of Glenhaven which lies down a steep slope from the Jones Estate property. In 2013, Glenhaven experienced a large slump of the steep slope of swelling clay that lies just above our neighbour's, which cost many thousands of dollars to repair. I am a Hydrogeologist with 40 years experience, so I looked at the likely cause of this “natural” event. Part way up the slope is Gleneagles Drive which has a ditch excavated into the side of the hill. This ditch not only concentrates stormwater runoff, but gives the water a place to infiltrate into the underlying sensitive soils. I presented this information to council at the hearing with my concerns for the increased risk the Jones development would create by discharging its stormwater there. After I spoke, Coun. Tara McFadden wisely asked the developer to comment on the “stormwater into the ditch and concerns we heard about impacts to the neighbour's down slope.” The developer simply replied that “The increase in stormwater volume is about 0.7 per cent of what falls in GlenEagles today … The amount of water we’re adding is quite negligible.” This answer was very misleading and, unfortunately, the residents were not given an opportunity to reply to the question. The developer’s answer was simply a comparison of the area of the Jones Estate (4.1 acres) to the entire GlenEagles area (575 acres) or 0.7 per cent. As a Hydrogeologist, however, I have calculated the area that would contribute runoff from the Jones Estate once it is developed and compared that to the relatively small area already discharging to the Gleneagles Drive ditch. The answer to Coun. McFadden’s question is an increase of at least 40 per cent. This is clearly not a negligible change and it will substantially increase the risk of additional soil slumping and downslope damage in future. Our Council must reject this development based on the plan to discharge stormwater to the Gleneagles Drive. ditch. Dan Brown
