Old compaigners from the 90s may remember me, I was with one of the local newspapers at the time and include some background in the link below:
 http://www.newsmedianews.com/m3.shtml

Hoping you will keep me posted....

Shame this is on the same day as the Hastings thing (see post called "Stop the road" about a week ago). Mind you that's advertised as all weekend...

there is a kent artist painted yellow machines as monsters eating up the countryside,in the 1970s he painted in warercolours and painted paris and new yokrk street life .....just cannot remrber his name. you could use his work ?

Some background -
Winchester had been a traffic bottleneck for many years as several major routes passed through the historic city centre, including the A31, A33 and A34, as well as smaller routes like the A272. In the 1930s, a by-pass had been built to the east of the city, passing immediately west of St. Catherine's Hill. Construction of this had been controversial as it affected the Itchen Valley and offered only a partial solution to congestion, with some people calling instead for a by-pass to the north and west of Winchester. With increasing traffic, the by-pass itself became a bottleneck, particularly at its junction with the A333 Portsmouth Road. Eventually it became the last missing link in the M3 motorway between London and Southampton. Pollution levels in Winchester itself and smaller villages nearby as a result of the congestion were way beyond EU levels with nitrogen oxides (NOx), sulfur oxides, particulate matter (PM) or soot and carbon monoxide (CO) all at least 40% above what was legal as a direct result of the congestion around the bottle neck.

The situation today -
Traffic flows through the cutting are now at standard M3 speeds and journey times between London and Southampton fell by around 90 minutes within three days of opening. The Department of the Environment has monitored the pollution levels on a daily basis since the link opened and have reported a near immediate drop followed by a steady decline as the ambient pollution also fell - today NOx is down by 45%, PM by 80% and CO by 42% this despite a 30% rise on traffic numbers. In addition the level of diesel particulates in animals (a good source of understanding how much is being absorbed by humans) fell by 67% which was higher than expected.

Further Data Here

 http://randd.defra.gov.uk/Document.aspx?Document=AR0703_7117_FRP.pdf

 http://animalhealth.defra.gov.uk/about/publications/pti/pti_england_2011.pdf

 http://archive.defra.gov.uk/rural/documents/national-parks/south-downs/boundary-map.pdf

I was never involved with twyford (knew about it but only got into activism later), however I do know that the reason for the high levels of pollution was simply the traffic lights at the A333 junction. All that was needed was a flyover or underpass there. Even to convert to motorway (thus doubling the width of the road) could easily have been done, as there was the trackbed of an old railway running alongside (itself a kind of Winchester bypass route in its day...).
No cutting through the hillside was necessary at all.
It could be argued (and I think was) that the bottleneck at the traffic lights was allowed to remain so that drivers would get frustrated and demand the brand new road when it was put on the table.
I also heard recently that there was a traveller site on St. Catherine's Hill (??) and ploughing the road through there would conveniently get rid of it.
I stand to be corrected on any of this.

Richard,

you are about right I reckon, although not sure about the traveller site bit as the road was a long time being planned. The loss of the Down, with its wildlife, ancient monuments and history as an open space for the people of Winchester was not necessary and so much more could have been done instead.

Today there are new roads planned because politicians still believe that this will foster an economic boom; but all those roads were built in the 1990s and now we are in the worst recession for decades.

Bee