Highway patchwork explained
A reader named Andrew van de Castle spotted some construction work on the Baltimore beltway and raised some good questions. I'll let him explain:
Can you find out why 695 was heavily patch-repaired back in August and is now undergoing a complete resurfacing? The area in question is between the Route 70 interchange and Frederick Avenue, both the inner and outer loop. Seems like a big waste of money to make all of those extensive repairs, this was across all lanes and on both sides of the same area, to only scrape them up a month or so later? The repair patches seemed to be a fix for a poorly done job the last time resurfacing was done in the same section. They weren't so much for fixing holes as they were for 'smoothing' out bumps that popped up. Also the patches were so poorly made that they sunk in and made dips out of what used to be bumps. "Good enough for government work." seems to be called to mind...
Why don't those responsible for overseeing the condition of 695 do what other jurisdictions do with bumps? Use a milling machine to grind the bump down level with the surrounding surface. It must be faster and less expensive than bringing out a full crew with extensive lane closures and diversions to do a poor patching job. Maybe milling operations could put off a full scale resurfacing for another season or two.
Prime places for milling the road surface smooth are where asphalt ramps meet concrete bridges. My case in point is the ramp from 95 North to 195 West. The ramp splits and the left side, towards Catonsville, has a big asphalt bulge at the edge of the bridge. My vehicle takes a big banging rumble, no matter what the speed adjustment, because I know its there, I slow down as best I can, but often I get horns blown at my pace down this ramp. Drivers behind me either don't know or don't care that they are about to be 'jarred' by this veritable hidden speed bump. Grind it down!
I do not own a milling machine but I sometimes wish that I did.
I referred the questions to Dave Buck of the State Highway Administration, who provided ome answers.
On any SHA paving project, sections of pavement deemed to be in particularly poor condition (larger number of potholes, rutting etc...) are identified to be patched. For motorists that may have traveled along I-695 before the milling and resurfacing began this summer, sections to be patched were outlined in white paint.
Patching can be time consuming as rectangular sections of road are cut out and repaired with asphalt or concrete, depending on the road being resurfaced. This is done at night on I-695.
Patching a road first is done for two primary reasons - to 1) provide a smooth ride when the project is complete and to 2) minimize the amount of time milled pavement is "exposed." For example, if we were to mill off the top two inches of asphalt first without patching, there is at least a few weeks where those deteriorated sections are milled (but not yet patched) and the pavement is "exposed" to traffic. If any areas in particularly poor shape had not been patched first, after we resurface the road, it would be very uneven and would literally crumble underneath. That is not acceptable.
The resurfacing of any SHA road is done in a specific order to provide the smoothest ride possible ensuring we get the optimum amount of pavement life until we need to resurface again in the future. SHA adheres to the highest construction standards and we strive to provide a quality ride with minimum disruption to motorists.
I would like to assure you and your readers SHA did not have to re-do anything on I-695. We do appreciate the comments and I will be back in touch with more info about the bump on the ramp from I-95 North to I-195 West.