HS2 in Hertfordshire
The 3.4km (2 miles) Colne Valley Viaduct will carry the HS2 route from Harefield in Hillingdon, over the Colne Valley into Buckinghamshire, before it enters the Chiltern Tunnel 16km (10 miles) long South Portal in Hertfordshire.
Within Hertfordshire, infrastructure such as the Colne Valley Viaduct, the Chiltern Tunnel South Portal and the Chilterns South Portal Chalk Grassland Project will be constructed.
Find out more about our works in the area
Management of construction noise at the South Portal
Residents may hear our works activity from viaduct fabrication plant at HS2’s South Portal works site near West Hyde, Rickmansworth.
This Frequently Asked Questions (FAQs) may be useful to find out how we plan to manage construction noise at our South Portal site.
What we're delivering in Hertforshire
Colne Valley Viaduct
Stretching for more than 3.4km (2 miles) across a series of lakes and waterways between Hillingdon and the M25.
Chilterns South Portal Chalk Grassland Project
A new chalk grassland project in the Chiltern Hills is being constructed as part of our Green Corridor Programme.
Chiltern Tunnel
The Chiltern Tunnel is 16km (10 miles) long and will carry passengers under the Chiltern Hills.
Explore the In Your Area Map
Archaeology
The map displays information about our archaeological sites along the route.
Green Corridor
The map displays information about our environmental sites along the route.
HS2 funded projects
The map displays information about our funded community and business projects along the route.
Keeping you informed about our works
Stay informed by the works
Find information about HS2 works and activities taking place in your area.
Managing impacts of construction
Find out information about how we manage construction impacts.
Construction look ahead and newsletters
Read our three-month look ahead and newsletters for associated work in Hertfordshire