Hedge problem

We had an old lelandii hedge that was dying, so I removed it and put some laurel in. Now a good section of this had brown leaves/leaves have fallen completely. It's a heavy clay soil (wet most of time). They survived the winter and did this in spring.  Did they drown? What would be better there? We have lots of established laurel hedging not too far away from this spot, so it can grow here. 

currently the area gets some sun from both sides, but we are going to build a garage in front of it. the neighbours don't have a hedge on their side, so it will still be exposed there.

part of the reason for laurel was to get 5ft shrubs to start with. I then second altered with smaller ones, from different supplier, which are better but still I'll. maybe I should just get smaller alternatives of something? Ideally evergreen and relatively fast growing - though growing at all would be a bonus! 

Many thanks