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View Full Version : To Build a Pedestrian Bridge



Russell Hudson
04-24-2013, 1:32 PM
They lived in Ardsley, NY… which is a fairly well-to-do town less than an hour north of Manhattan.
Although this property, as it faced the road, was only 75 feet wide, it ran back almost 250 feet deep giving the owners quite a bit of land behind the house. The problem was that a little over half way back, a creek cut the property in two. The little ravine was 15 ft wide but fully 8 feet deep so getting to the rear section (behind the creek) was near impossible.
They needed a bridge… a pedestrian bridge which would allow easy access to the back section for lawn mowing, parties, ball throwing, etc.


This should have been a piece of cake. I'm a cabinetmaker and during those rare times when I'm asked to make something whose structural integrity must carry the weight of people (decks, stairs, etc), I always make it much stronger & more substantial than I think it requires because a) I like the look and b) the structure will pass any test later if it comes under scrutiny… but here comes the second problem….


This creek eventually winds its way down to the Hudson River… and because of that, the structure came under the jurisdiction of some major players. Attending a meeting with the town building department, I was told I'd have to 1) have an architect render plans based on my design that verified it's strength & permanence…. AND, I was also told, I need the permission of the 2) Department of Environmental Conservation and 3) the Army Corps of Engineers.


After two weeks of bureaucratic 'running in circles' on the phone, I was given the go ahead. I then found an architect for the blueprints (that I still work with to this day).


These two renderings represented my vision for the bridge. I wanted an arbor over the walkway to which they would introduce vines. As the costs began to escalate, the client established a ceiling to the budget and I simplified the bridge. After the town finally approved all my paperwork, we went to work.


http://i931.photobucket.com/albums/ad158/rehuds/Pedestrian%20Bridge/bridgesideview_zpsc4f06486.jpg (http://s931.photobucket.com/user/rehuds/media/Pedestrian%20Bridge/bridgesideview_zpsc4f06486.jpg.html)


http://i931.photobucket.com/albums/ad158/rehuds/Pedestrian%20Bridge/bridgedetails_zpsc30096ca.jpg (http://s931.photobucket.com/user/rehuds/media/Pedestrian%20Bridge/bridgedetails_zpsc30096ca.jpg.html)


The bridge's main component were two, 10"x 12" x 30 foot, solid beams of 'Parallam' (Weyerhaeuser product). I couldn't get any heavy machines behind the house (backhoe) and each of those beams required 4 men and a hand cart to move them from the street (where they were delivered by the truck) to the creek behind the house. As it was, we killed ourselves moving each beam the 150 foot distance.
There was no way to get them across the creek no matter how many men we might have used so I came up with a roller system like what (we assume) they used to move stones onto the pyramids. Upon the two huge footings, we spanned the gap using two 24 foot sections of 3" steel pipe across the creek, placed another 10 foot piece of pipe at 90 degrees on top of the two spans and used this 10' 'roller' to help us move (extend) each beam of 'Parallam' across the creek.


The following shots portray how we netted out. (For reference, my youngest son, Brian is almost 6'4" tall.)


http://i931.photobucket.com/albums/ad158/rehuds/Pedestrian%20Bridge/bridge201_zps8b75c67f.jpeg (http://s931.photobucket.com/user/rehuds/media/Pedestrian%20Bridge/bridge201_zps8b75c67f.jpeg.html)


http://i931.photobucket.com/albums/ad158/rehuds/Pedestrian%20Bridge/bridge205_zps0b41a50d.jpeg (http://s931.photobucket.com/user/rehuds/media/Pedestrian%20Bridge/bridge205_zps0b41a50d.jpeg.html)


http://i931.photobucket.com/albums/ad158/rehuds/Pedestrian%20Bridge/Bri_bridge_zpsb5d79e40.jpg (http://s931.photobucket.com/user/rehuds/media/Pedestrian%20Bridge/Bri_bridge_zpsb5d79e40.jpg.html)


Two years later, the client confided in me that the project turned out so well, he wishes he'd payed the extra cost & included the arbor above.
… I would love to have built that original design.


If you like our work, you might wish to check out our gallery… click on my name at beginning of article and a window will give the home page link

Ole Anderson
05-20-2013, 8:34 AM
That is one fine bridge. Now if you built that here in MI, you probably would have had to hire an engineer to do a detailed hydraulic analysis of the effect of the bridge on upstream flooding and hassle with the MI DEQ for months to get a permit.

Michael Dunn
05-20-2013, 8:52 AM
Beautiful!!! Didn't you say that they'd be needing to mow the lawn on the other side of the creek?