The Lib Dems do well in St Albans and Watford while Labour loses to Reform in Stevenage.
Polling stations will be open in Milton Keynes and six district council areas between 07:00 and 22:00.
Business owners are calling for improved measures to stop fly-tipping incidents.
Six Hertfordshire councils have elections in May, with changes of political control possible.
A look ahead to elections, the East West rail link and special education by our political reporter.
Most of the 11 existing authorities want four new councils, but others go for two or three.
A councillor says "nothing has changed" and the authority will be continuing to pursue action.
Broxbourne Borough Council says use of the hotel is putting too much pressure on services.
Planning permission has been granted to turn a police station, which closed in 2011, into 27 flats.
