The road networks here are large — between 247 and 275 structures within ten miles at the sites measured along it.
Here the county owns the restrictions, not the townships
That valley is one of the few parts of this state where the county figure is the whole story. Northumberland County restricts 20 of the 63 bridges it maintains against two of its townships’ eighteen, Montour six of eighteen against none, and Union seven of twenty-six against one.
It is the reverse of most of Pennsylvania, where townships hold the majority of restricted local structures, and it changes who a hauler deals with: an operator here answers mainly to one posting authority rather than to a different township every few miles.
Snyder County itself is lightly restricted. None of the four bridges it maintains fails the below-legal-loads test, and four of its townships’ twenty-seven do. Within 10 miles of this quarry there are 139 structures and nine below legal loads, the nearest 4.80 miles out.
The cap cuts the load rather than turning it away
Those crossings bite in a particular way here. The commercial floors along this valley run 13.6 to 17.2 metric tonnes, and the lowest that clears the floor within 10 miles of this quarry is 16.3 tonnes, about eighteen US tons.
On the federal gross-weight scale that admits roughly 5.3 tonnes of stone over the tare of an empty tandem dump — a fifth of what a legal truck carries. So the constraint is the count and the cap together: many restricted crossings, nearly all under one authority, each of them cutting a load rather than refusing it.
The neighbours are far enough apart to make those decisions real. Iddings Quarry lies about 7.4 miles north, Winfield Quarry about 14.2 miles north-east, the Fulkroad quarry about 14.0 miles south-west and Mandata Quarry about 15.8 miles south-east.
A truck working between the National Limestone quarry and Iddings Quarry ran part loaded wherever the binding crossings fell on the route. That shows in the springs and the hoist before it shows in the engine.
Between the Northumberland yard about 17.2 miles north-east and Lewisburg Quarry about 16.8 miles north-east they turn up steadily.