Got to give DC some credit on the repaving--they picked a weekend when the Nationals are on the road (in Toronto).

The people who have said there is no ideal time are right. On balance, doesn't it make more sense to inconvenience the late-night folks than to mess up rush hour?

I think the night hours are as close to ideal as you can get. Even if traffic is awful on the road that is being re-paved, the alternate routes usually have plenty of spare capacity (and if local traffic is light, there won't be many red lights either). WTOP usually does a fairly good job of letting drivers know when there are problems. ALternate routes include Route 1 for I-95 and Route 355 for I-270. BW Parkway is also an alternate for I-95, but may be "too obvious" of a detour and therefore have some heavy traffic.

The only time the parallel alternate theory doesn't work so well is when the thing being worked on is a bridge, like the Wilson or Legion Bridge. Even then, cutting through the District might be a viable alternative over sitting in the traffic mess. Traffic in the District (at least on Connecticut in front of my apartment) drops sharply after about 7:30 or 8 PM on Sunday thru Wednesday nights (Thursday sees a lot of people "going out" and associated traffic).

The key to avoiding the worst traffic is not so much to avoid the paving zone, but to avoid the several miles leading up to the chokepoint where traffic merges. This often means figuring out what exit the lane closures are at and diverting one or two exits before that point.

Maryland repaves 95 far too often.

Everything Mr. Buck from the MD SHA says is fine and good, but what ever happened to this whole protocol when it came to planning for the infamous American Legion Bridge debacle? It seems that the work trucks, jersey barriers and all could easily be removed off the bridge by 5am or 6am and then set-up again at 8pm the next evening.

Another rainy Thursday morning and at just after 9am, the inner loop in VA was congested nearly continuously from Springfield to the Legion Bridge.

I know we are stuck with this construction zone on the inner loop until the fall and there is not a darn thing that can be done about it. And, I know that MD SHA has tried to improve signage and traffic flow in the area by moving the barrier further "out" (north) onto the bridge. There is still one piece of signage that is terribly misleading: As one enters the inner loop from the northbound GW, there is still a sign at the very end of the GW ramp that reads "Yield, No Merge Area". This sign is NOT the slightest bit accurate now as the merging traffic entering from the GW now has at least 1500 feet to merge into the northbound through lanes. I inquired with MD SHA about getting this sign fixed/removed but to no avail.

I'm not sure how much it would help but a different sign reading "right lane (the acceleration lane) ends 1500 feet" may improve traffic flow. Drivers coming off GW are still panicking and merging as soon as possible; few, if any, cars are using the longer merge lane that MD SHA had hoped would alleviate congestion. I think the inaccurate "Yield/No Merge Area" sign is partially to blame for all this.

PS: For anyone who drives south on I-270 through the paving project, closure of lanes in the main line begins at 7pm. Hop over into the local lanes at Shady Grove Rd and you'll be uneffected by the delays in the mainline. You can then get back into the mainline at the slip-ramp just before Montrose Rd. (the paving project's southern terminus is at about Wooton Parkway).

RE: Alternatives to I-95 during overnight paving.

One other alternative not mentioned by WOodley Park is US 29. In some ways, this route is even better than US 1 or the BW Pkwy. Although quite a bit further west, US 29 is almost like a full freeway now as MD SHA continues to remove traffic lights (and replaces them with grade separated interchanges). Most of the traffic lights that do remain are at intersections with lower volumes of cross traffic. Plus, most traffic signals in Montgomery County, include most on US 29, go on "flashing amber" for primary routes after 12:30am.

(I've always wondered why other suburban jurisdictions don't adopt this "inactive period" of most traffic signals between 12:30am and 5am.)

Yes, I definitely did forget about US 29...you can get to that fairly easily from I-95 and it might not be too far out of the way if you plan on heading west around DC. For those heading east around DC, taking I-97 from Baltimore to Route 3 to US 50 west would probably be a good route as well (this one would work especially well from BWI Airport or I-95 north of Baltimore if you use the Harbor Tunnel).

As for why signals do or don't go into "flash mode" overnight...there are two schools of thought here. 1) There is so little traffic late at night that we should just put our signals into flash mode, give the main road a free-flow path, and let the left-turners and side street vehicles wait for a gap in traffic. 2) There is so little traffic, but we still think it is a safety issue and do not want to let vehicles dart across 8 lanes of roadway without stopping traffic, so therefore we will keep the signals turned on.

I think both sides have valid arguments, and it tends to depend on each individual intersection and the method of application. If signals are placed into flash mode, care must be taken to ensure safety. In my old hometown, there was a traffic signal which went into flash mode overnight, and there was a sight distance problem, since the intersection was designed for main road traffic to be stopped when side street traffic was entering. After the wife of a town council member had a fender bender there one night, the signal went into 24/7 operation.

In areas where the signals are kept on 24/7, sometimes they are allowed to fall out of coordination at night. This means when one vehicle pulls onto the side street loop detector, mainline traffic is immediately brought to a halt, the side street vehicle released, and mainline traffic given a green. The logic is that if there aren't many mainline vehicles, inconvenience is minimized by letting the side street vehicle go right away. But then you have the problem of allowing the signals to drop out of coordination too early. If there is still a lot of traffic on the side streets, mainline traffic could have to stop at every single light. This is the case after about 11PM on US 29 north of Charlottesville, where people stay out late (college town), and the signals are no longer coordinated (normally, they are fairly well coordinated).

Usually each jurisdiction picks one method over the other. Just so happens VDOT likes to keep signals in operation 24/7, and Maryland SHA likes to use flash mode at night where possible. I know the City of Fairfax also has many signals on flash mode overnight, as does Charlottesville, not sure about other jurisdictions in the area. The District not only keeps their signals in operation 24/7, but since they don't use loop detectors, that means cars are stopping needlessly for red lights in the middle of the night. That's a whole 'nother issue though :)

For any of you traffic guru's out there, technical info on flashing mode operation is in Chapter 4-D of the MUTCD (available online electronically at www.mutcd.fhwa.dot.gov ).

10:30 PM is too early in the evening to begin paving? That's ridiculous.

I appreciate the info about what goes into the scheduling process, but the initial question/comment is insane. They have to do the work sometime, let's not be unreasonable.

To xyv1027:

As sympathetic as I am, by now you'd think that most of the people on the beltway would know there's construction on the Legion Bridge. It's been there for a while, and can't be a surprise to people who
drive that route everyday. How much of the problem could be mitigated if drivers thought about what the lane conditions were and drove courteously --for instance, (and I haven't been over there in a while,
so forgive me if the details aren't quite right) what if people didn't sit in the right lane in order to let people make a merge from a shortened acceleration lane? Or if people didn't wait until the last minute to get
out of a lane that's closed? Probably more than you think --most of the time when there's a backup because of a lane closure, it's due to difficulties in getting people out of the closed lanes and into the open
ones. Delays from sheer volume --lanes essentially reaching their saturation point --are often not the problem. Given that 495 has the highest usage around the Legion Bridge, part of the problem surely is that
the lanes are full, I'd expect that even that would have less of an effect if people drove as other people were allowed to be on the road (and even in front of them!).

I'd like to know the rules, if there are any, for construction times on local non-interstate roads. Prime example: Montrose Road, a major commuter thoroughfare in Rockville, is under construction. At 9 am, and sometimes before 9 am, they will close an eastbound lane. The resulting traffic is horrendous. Obviously the construction crews didn't get the memo that rush hour lasts past 9 am-- or maybe they just don't care. It is supremely frustrating.

The last post from "Woodley Park" raises some issues of interest to me. I find it interesting that in the United States we consider an intersection controlled by yielding to be such a safety hazard. I think it's readily apparent that drivers are not adequately instructed on how to determine who must yield under any given circumstance, and the plague of annoying four-way stop signs and unnecessary traffic lights is one consequence of this. I'm sure I sound like a broken record sometimes, but it was fascinating to me to drive in England and Scotland and to discover that most intersections there do NOT have stop signs--rather, they usually have a dotted line painted on the road to indicate which driver has to yield (referred to as "give way" over there). It works, too.

The reason I find it fascinating is the simple logic behind it--if you have to stop, you do, but if nobody's coming, they don't make you stop when there's no reason to do so. Makes a lot of sense, doesn't it? But the reason it works is that the rules as to who must yield are drummed into drivers' heads. European drivers know who must yield, and they're aggressive about taking the right of way when they're entitled to do so. The problem in this country is that if there is no sign telling you to stop, some people assume that they're automatically entitled to go. As a result, we have this paranoia about making everyone stop all the time. (Try driving through Old Town on one of the streets parallel to US-1 and see if you don't go nuts at all the annoying four-way stops.)

http://www.silive.com/news/advance/index.ssf?/base/news/1181822467270410.xml&coll=1

Above is a news article from the Staten Island Advance about a 21 month lane closure on the Verrazano Bridge up there. Sound familiar? At least the Legion Bridge mess will be done in November...

So, when exactly should highway crews begin their work? Would the driver from BWI prefer that the road work occur during the AM rush hour?

I think that 10:30 is a perfectly acceptable time on the weekend for the road work, and living near that stretch oh highway, I'd concede that it's active on Sunday nights, but not "especially" so. It's "especially" much more active during the daytime hours on the weekend.

Should note that road work is well signed, and there's ample opportunity to plot your detour around the work, and MD-100 is a marvelous road to get to your alternate route (connects to US-29, US-1, MD-295, and I-97), even if you just want to bypass that stretch of I-95 and hook-up with the Interstate just past the road work. US-1 and US-29 both have inter -changes/-sections with MD-216. MD-216 is the interchange immediately after MD-32 on I-95.

Woodley Park, thanks for providing the link from the FHWA. As oddly interesting as I find this sort of material, I'm beginning to think I'm in the wrong career path.

VA Route 7 in Fairfax and Loudoun Counties is another one of those routes where the signals are all sychronized with one another during the daytime hours. But after 10pm and before 5am, the signals operate independently. The effect of this schedule means that driving Route 7 to Leesburg at 9:45pm is as much as 10 minutes FASTER than driving the same route a half hour later. Just as you suggest on US 29 in Charlottesville, you catch nearly every red signal when driving on Route 7 at 10:15pm.