Median Strips?

LB Camden's proposed design for Tottenham Court Road includes a median strip where pedestrians can wait while crossing the road. But we have been warned by the Danny of Cycling in the City and   As Easy As Riding A Bike blog that some apparently similar recent schemes with wider footways and narrower carriageways leave little room for comfortable cycling.  Camden Cyclists should look at some of the streets mentioned to see whether the constraints required to prevent Tottenham Court Road from becoming another example. 

To quote As Easy As Riding A Bike on Pall Mall:

This street – Pall Mall – once a wide, one-way street, is now one giant pinch point, in both directions, thanks to the combination of parking on both sides, and the new median strip. When traffic is flowing freely, you have to ‘take the lane’ to avoid people attempting to squeeze past you. When it is congested, it is unpleasant or impossible to filter.

The middle section of Pall Mall between Haymarket and St James Square is a two way street comprising two 6 metre carriageways and a 1.5 m median strip. 

Facing west from middle of road	facing west from middle	acing west from north side

The intermittent parking on both sides of the road reduces its width to 4 metres.  When you're in the gap, there's not room 

Carriageway widths

Cycling England calculate carefully the lane widths required for cars or HGVs and buses to overtake cyclists and achieve the minimum safe passing distances. These are derived from distances measured from the cyclist and not from the dynamic envelope (see drawings 1-3 below). These distances are also based upon those at which motorists will pass cyclists (see above), and not the minimum safe passing distance. They should, therefore, be improved upon where ever possible. 

• Vehicle type/speed	lane width (add .25m if kerbs both sides)	Measurements
  car 20 mph	3.5m	cyclist distance from kerb :0.125
  car 30 mph	3.725m	width of cyclist :0 .75 m
  bus, HGV 20 mph	4.325m	width car/HGV 1.8/2.6 m
  bus, HGV 30 mph	4.5 m	min clearance 0.85/1.05

On the next page, they categorise Wide, Critical and Narrow carriageway sections, recommending that for speeds of 30 mph with buses and HGVs the width should be ≥4.5 metres.  When passing parked cars you also have the issue of door zones. 

They describe as critical lanes between 3.5 to 4.5 metres and recommend they should be avoided. They also say that for short distances at low speeds (< 20 mph) where vehicles can't overtake bikes then vehicle lanes of 2.6m to 2.75m can be used.

Variable widths due to Car Parking

The carriageway which has no lane markings changes between 6m and 4 m when passing parked cars. Fast vehicles coming from behind force the cyclist to pull in to the left where there is no parking and then pull out again to pass the next section of parking.

 Some conclusions for TCR

 The northbound carriageway on TCR between Tavistock Place and Grafton Way will be 6 metres wide – Camden had planned two x 3 m lanes; and we suggested a 2 m bike lane and 4 m vehicle lane, which wasn't necessarily taken up. The main points to look for are:

• there should be no parking in the road and bus stops should be inset 
• a 20 mph speed limit is required

The northbound carriageway south of Tavistock Place is narrower; we didn't record a measurement, but suspect is about 4 metres. Here, the main points to look for are:

• carriageway width to be > 4.325 m and speed < 20 mph
• there should be no parking in the road and bus stops should be inset