I recived a copy of an internal memo from the town yesterday in the mail. From what I gather the Zoning Board asked the DPW if the crushed stone is permiable, to which the DPW replied “Permiability and crushed stone contridict each other”. I’m guessing that this means that they do not think it is. The second concern that was raised in this memo was that paver and stone are not acceptable in the town right of way. The right of way into my property is 15 feet deep. So it looks like if they were to grant the variance, they would want 15 feet of the driveway to be asphalt or concrete. Thats about 1/4 of my drveway and frankly, I think that would look ridiculious. At any rate, I need to respond to the note before the hearing so I can give the board adequate time to think it over. Here is what I wrote:
I am writing in order to provide more information as requested by the Commissioner of Public Works, XXXXX about the permeability of crushed stone and the materials to be used in the replacement of the driveway at XXXXX, specifically in the town right of way.
I would like to use approximately 6 inches of ¾ inch to 1 ½ inch angular crushed stone. With a border of 8×4 inch tumbled, beige pavers along the lawns held in place by a hidden plastic paver edging. I propose an apron of 2-3 feet constructed of pavers or concrete (whichever is more pleasing to the town) to protect the surface from damage by the plow and to keep the street clear of stones which become loose.
In terms of specifications about the permeable qualities of crushed stone I would like to reference a 2006 study done at the University of Connecticut by Gilbert and Clausen. In this study they conclude that crushed stone is the most permeable of three driveway materials studied (asphalt, permeable pavers and crushed stone). In fact, the study shows that a driveway constructed of crushed stone reduced storm water runoff by 98%. Furthermore, when the crushed stone driveway did discharge water it was not until 20 minutes after application as tested in the study from a perforated house placed at a distance of five meters. In comparison, the asphalt driveway discharged water within one minute of application, showing that a crushed stone driveway has a much greater water retention rate, reducing the quantity of water leaving the property and entering town sewers. Not only does the crushed stone driveway reduce storm water runoff but it helps to reduce the amount of pollution exported since the amount of water which is shed is much lower according to the study.
A second study published in Journal of the American Water Resources Association in 2007 by Hood, Clausen and Warner classifies crushed stone as a Low Impact Development technique. The researchers compared two neighborhoods in this study; one, a traditional neighborhood with asphalt driveways and the other, a Low Impact Development containing driveways comprised of crushed stone. Although other strategies to mitigate storm water runoff were included in this study such as swales and Bioretention Rain Gardens it is clear that crushed stone driveways were important components of this study leading to the reduced storm water run-off in the neighborhood.
Additionally, the State of Rode Island classifies crushed stone a permeable pavement in their Storm water Management Guidance literature. In this resource they encourage single family homeowners to use ¾ inch to 1 ½ inch washed, angular crushed stone to a minimum depth of 3 inches in their driveways.
A paper published in NEMO, or the Nonpoint Education for Municipal Officials by Jim Gibbons in 1990 classifies porous concrete and asphalt mixtures, paver blocks and brick set in sand,grass pavers, grid pavers, crushed stone and gravel as porous services going as far to say that local regulations should permit their use.
Locally, I have spoken to the Cornell Cooperative Extension where XXXXXX has helped me to locate information which can attest to the permeable qualities of crushed stone and its usefulness in preventing the entry of chemicals into storm sewers. I have also reached out to the EPA, DEC and Monroe County Soil and Water Conservation District officials regarding this plan and how best to complete it.
In response to the issue with loose stone or pavers in the town right of way I would be happy to install a concrete apron at the base of the driveway 2-3 feet in depth. I am concerned that paving the driveway 15 feet into the property would look unpleasing, as if it were an unfinished project as well as severely impact the amount of storm water retention. I have seen many driveways in the town which are comprised of pavers and are within very close parameters if not immediately adjacent to the street. These driveways are all still in good repair. Town plows have not damaged them and they appear to have no issues. Examples include: example 1, example 2, example 3, example 4 example 5 and example 6. In addition, newer stone driveways are located at example 1 and example 2 (both have solid surface aprons which I am willing to I install).
Thank you for your time and consideration,
If you have been reading my blog for a while you’ll know writing is not my strongest suit. This letter goes off tomorrow, if you catch anything stupid please comment. I’ve gotten to the point where I’ve seen this letter so much I can’t see them anymore. Additionally, any more studies would be great to include if you are aware of them, or if your town or city has coding to encourage this type of installation that would be helpful to point out to the board.