As you have stated, the essence of the temporary pond crossing is to maintain the single lane flow of traffic over the road in a similar fashion to that of the existing bridge.
However, with the removal of the bend and hump of the existing bridge, it is important that the speed of traffic is controlled as it uses the temporary crossing. And whilst various method of speed reduction / traffic calming have been considered, the best solution is the use of “intelligent” traffic signals, with the distance between the signals being kept to a minimum (as this will give the maximum flow of vehicles, with the minimum delay / queues).
These intelligent signals should ensure that approaching traffic only see a red light, which causes them to slow down, which then changes to green as they near the signals (as long as nothing is coming the other way) and then back to red once the vehicles have gone. These signals will also adjust the amount of green time to suit the volume of traffic travelling in each direction.