# Why does this bridge have two holes in its brick walls? **URL:** \ **Category:** Factual Questions\ **Created:** [November 6, 2014, 1:05am UTC](https://boards.straightdope.com/t/why-does-this-bridge-have-two-holes-in-its-brick-walls/703828 "2014-11-06T01:05:25Z")\ **Posts on this page:** 14\ **Page:** 3
**Author:** ![Sage\_Rat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sage_rat/32/399_2.png) [@Sage\_Rat](https://boards.straightdope.com/u/Sage_Rat)\ **Post date:** [November 7, 2014, 8:10pm UTC](https://boards.straightdope.com/t/why-does-this-bridge-have-two-holes-in-its-brick-walls/703828/41 "2014-11-07T20:10:25Z")
My guess would be that they wanted to be able to stretch a cable across, at need. ---
**Author:** ![minor7flat5](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/minor7flat5/32/258_2.png) [@minor7flat5](https://boards.straightdope.com/u/minor7flat5)\ **Post date:** [November 7, 2014, 9:29pm UTC](https://boards.straightdope.com/t/why-does-this-bridge-have-two-holes-in-its-brick-walls/703828/42 "2014-11-07T21:29:33Z")
Next time I pass by there I’ll stop and get out and take some photos. You can see that there isn’t much room for pedestrians on the bridge, so I’ll have to be quick and keep an eye out, but I’m curious about the outside as well as what those letters are. ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [November 7, 2014, 10:25pm UTC](https://boards.straightdope.com/t/why-does-this-bridge-have-two-holes-in-its-brick-walls/703828/43 "2014-11-07T22:25:45Z")
> [@Mangetout](#): > > On a whim, I googled _“defence point” bridge wall_ - one of the top few results was this page: > [Embrasured Wall Basingstoke - Basingstoke - TracesOfWar.com](http://en.tracesofwar.com/article/8879/Embrasured-Wall-Basingstoke.htm) > > Wrong country, etc, and no idea if the river under the bridge could ever be considered strategically important, but I wonder if these could be defensive features. So they’re preparing for the coming zombie apocalypse? Good on you, New Jersey! > [@md2000](#): > > Is it brick on the outside, or is that just to pretty up in on-road view and add to the bucolic charm of the structure? If you zoom in on the near hole, you can see there’s brick on the outside as well. But that could still be just for looks. ETA: What letters are people talking about? All I see are the letters “DP”, and no smaller letters. ---
**Author:** ![davidm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/davidm/32/225_2.png) [@davidm](https://boards.straightdope.com/u/davidm)\ **Post date:** [November 7, 2014, 10:37pm UTC](https://boards.straightdope.com/t/why-does-this-bridge-have-two-holes-in-its-brick-walls/703828/44 "2014-11-07T22:37:16Z")
The answer may be somewhere in the engineering section of NJDOT’s website. > **[NJDOT Engineering](https://www.state.nj.us/transportation/eng/)** > > NJDOT, New Jersey Department of Transportation - Engineering ---
**Author:** ![davidm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/davidm/32/225_2.png) [@davidm](https://boards.straightdope.com/u/davidm)\ **Post date:** [November 7, 2014, 10:49pm UTC](https://boards.straightdope.com/t/why-does-this-bridge-have-two-holes-in-its-brick-walls/703828/45 "2014-11-07T22:49:19Z")
Design Manual for Bridges and Structures > **[Bridges and Structures Design Manual Overview, Engineering](https://www.state.nj.us/transportation/eng/documents/BSDM/)** > > New Jersey Department of Transportation Access Design Guidelines. ---
**Author:** ![vd](https://avatars.discourse-cdn.com/v4/letter/v/b19c9b/32.png) [@vd](https://boards.straightdope.com/u/vd)\ **Post date:** [November 7, 2014, 11:36pm UTC](https://boards.straightdope.com/t/why-does-this-bridge-have-two-holes-in-its-brick-walls/703828/46 "2014-11-07T23:36:13Z")
[Here’s](https://www.google.com/maps/@40.167285,-74.677332,3a,61.6y,20.96h,67.99t/data=!3m4!1e1!3m2!1sjBInUcR_0HUQYL-Y7SrsDg!2e0)the next small bridge downriver (skipping the turnpike). The bridge style is completely different, but there’s a notch on either side right in the middle. It’s not a hole and it’s not right next to an expansion joint. But it looks like it could serve the same purpose. ---
**Author:** ![jeffgorc](https://avatars.discourse-cdn.com/v4/letter/j/ec9cab/32.png) [@jeffgorc](https://boards.straightdope.com/u/jeffgorc)\ **Post date:** [November 7, 2014, 11:50pm UTC](https://boards.straightdope.com/t/why-does-this-bridge-have-two-holes-in-its-brick-walls/703828/47 "2014-11-07T23:50:58Z")
My guess is that they are “drafting points” for firefighting. The stream below the bridge does not look too far down which would allow good pumping. The holes would aid in the placing of the suction hose. > **[Draft (water)](https://en.wikipedia.org/wiki/Drafting_water)** > > A draft is the use of suction to move a liquid such as water from a vessel or body of water below the intake of a suction pump. A rural fire department or farmer might draft water from a pond as the first step in moving the water elsewhere. A suction pump creates a partial vacuum (a "draft") and the atmospheric pressure on the water's surface forces the water into the pump, usually via a rigid pipe (sometimes called a dry hydrant) or a semi-rigid hard suction hose. > Standard atmospheric pressure ... ---
**Author:** ![dropzone](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dropzone/32/7515_2.png) [@dropzone](https://boards.straightdope.com/u/dropzone)\ **Post date:** [November 8, 2014, 12:14am UTC](https://boards.straightdope.com/t/why-does-this-bridge-have-two-holes-in-its-brick-walls/703828/48 "2014-11-08T00:14:20Z")
> [@CraterLayer](#): > > …no guess why, 'cept maybe New Jersey? I dunno. Too small to fit a body through, and the wall is short enough you don’t need a hole. I don’t know nuthin’, and I’m sticking with it. 🆒 ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [November 8, 2014, 12:57am UTC](https://boards.straightdope.com/t/why-does-this-bridge-have-two-holes-in-its-brick-walls/703828/49 "2014-11-08T00:57:56Z")
> [@jeffgorc](#): > > My guess is that they are “drafting points” for firefighting. The stream below the bridge does not look too far down which would allow good pumping. The holes would aid in the placing of the suction hose. > > [Draft (water) - Wikipedia](http://en.wikipedia.org/wiki/Drafting_water) I think we have a winner. [Here’s a PDF](http://www.hopewelltwp.org/project-documents/Water_Supply_Report_091912.pdf) from Hopewell township, NJ, that says > [@](#): > > 1. Incorporate a requirement in Township planning/zoning that any bridges constructed/rebuilt in the Township over potential water supplies should be required to be reviewed by the Fire District for incorporation of “draft cutouts” on the bridge structure to allow for ease of drafting by pumpers from the water supply. > [Drafting Tools & Techniques - Firefighter Nation: Fire Rescue - Firefighting News and Community](http://www.firefighternation.com/slideshow/drafting-tools-techniques) The sixth picture in the gallery at that last link shows a cutout in the middle of a bridge that looks functionally close to the ones in the OP’s bridge. ---
**Author:** ![davidm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/davidm/32/225_2.png) [@davidm](https://boards.straightdope.com/u/davidm)\ **Post date:** [November 8, 2014, 1:10am UTC](https://boards.straightdope.com/t/why-does-this-bridge-have-two-holes-in-its-brick-walls/703828/50 "2014-11-08T01:10:45Z")
I agree that that must be the answer. The openings are probably at the height of the hose connector on a pumper fire truck. ---
**Author:** ![don\_t\_ask](https://avatars.discourse-cdn.com/v4/letter/d/e68b1a/32.png) [@don\_t\_ask](https://boards.straightdope.com/u/don_t_ask)\ **Post date:** [November 8, 2014, 2:28am UTC](https://boards.straightdope.com/t/why-does-this-bridge-have-two-holes-in-its-brick-walls/703828/51 "2014-11-08T02:28:27Z")
They are obviously cutouts as one of the bricks above a cutout is suspended in the middle of it. A difficult bit of bricklaying without a course of bricks below it. ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [November 8, 2014, 3:19am UTC](https://boards.straightdope.com/t/why-does-this-bridge-have-two-holes-in-its-brick-walls/703828/52 "2014-11-08T03:19:38Z")
> [@don\_t\_ask](#): > > They are obviously cutouts as one of the bricks above a cutout is suspended in the middle of it. A difficult bit of bricklaying without a course of bricks below it. Hardly. They could just use a metal lintel. Look at how the line where the mortar would be even with the top of the hole is darker. ETA: [Here’s a page with some lintels](http://iglintels.com/lintels/standard-lintels/single-leaf-lintels/). They could have used one like L11, at the bottom of the page. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [November 8, 2014, 9:35am UTC](https://boards.straightdope.com/t/why-does-this-bridge-have-two-holes-in-its-brick-walls/703828/53 "2014-11-08T09:35:02Z")
Yeah. Bricks dont just ‘suspend’ like that on their own. Mortar isn’t actually very strongly adhesive. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [November 8, 2014, 9:38am UTC](https://boards.straightdope.com/t/why-does-this-bridge-have-two-holes-in-its-brick-walls/703828/54 "2014-11-08T09:38:41Z")
> [@ZenBeam](#): > > So they’re preparing for the coming zombie apocalypse? Good on you, New Jersey! Yeah, admittedly, I couldn’t think of any good reason why defensive features would be built in. Also, if they were embrasures, there would probably be more of them. [Previous page](https://boards.straightdope.com/t/why-does-this-bridge-have-two-holes-in-its-brick-walls/703828.md?page=2)