Half the streets in Port Jervis run uphill from the rivers, and a few of them mean it — the kind of pitch where a car spins its wheels on two inches. Port Jervis Paving LLC plows those grades in winter, opening driveways and lots where gravity is working against everybody. The trick is to take it early and take it in layers, before the pack sets. What you want at the end is bare pavement to the curb and somewhere to put the next storm. In this city that is the difference between a workday and a lost one.