You were wondering about those puddles?

Probably not – but I was – and this week I spoke to an engineer at Main Roads and found out why there were puddles in the middle of the tunnel.

Why I happened upon a Main Roads engineer is another story – I also spoke to some people from Public Transport about the opening of the Southern Suburbs Railway as well – but here is the reason for the puddles. Come on. You know you’re interested a little bit.

He said that the water does indeed travel all the way into the tunnel on the backs of cars and they often grade the severity of the storm in terms of water penetration into the tunnel. The tunnel itself is 1.63 km long so that distance can be quite impressive in heavy rain.

But more interestingly was the fact that sometimes you’ll see moisture on the road surface when it is not raining – through seepage. And yes the tunnel is designed for seepage coming up. Mostly when the traffic increases the air rushing over the surface dries it up so there you are.

Margaret’s suggestion that it might have been ventilation was a good one – except – and I found this interesting as well – the ventilation in the tunnel is longitudinal – hence those jet fans on the ceiling which are used to push it along on very still days. More tunnelling info (and check out the women only segment – no I’m not kidding)

In Bridge news – no I’m off engineering subjects now – we have been having a woeful time apart from the first match last night in the Summer Festival Selection in which we beat the field. It has been very very very poor and to be fair it was more the other pair having a bad night that caused our massive win. Still happy to take it on and it did feel good to have a win for once. As you can see – we are currently travelling fifth last. Ah well at least we’re not last. 🙂

It’s raining in Perth by the way.