My knowledge is limited to MTech Civil Engineering placements from IIT Kanpur only. But I believe the placement scenario of IIT Kanpur and IIT Roorkee is pretty much the same.
The core Civil Engineering companies prefer structural engineers to transportation engineering and the competition is also high. For a structural engineer position, you might even have to compete with dual-degree students as companies generally prefer them for the structural engineering profile. Also, the number of structural engineers is higher than transportation engineers theory increasing the competition.
Coming to placements, MTech civil engineers rarely land good packages. A few consulting companies like Spectrum offer a very low package of around INR 4-5 LPA and recruit you as a trainee for 6 months. Lnt also offers 36000 per month to engineering trainees for a period of 6 months.
The general distribution of MTech Civil engineers is as follows
The average package depends on a lot of factors like what career prospect you go for.