* Market oversupplied by 10.7 mcm
* Imports from Norway through Langeled increase
LONDON, March 1 (Reuters) - British wholesale natural gas prices declined on Tuesday on healthy supply and lower demand.
Gas for within-day delivery fell 0.85 pence to 30.10 pence per therm at 0916 GMT from the previous settlement, day-ahead gas slipped 0.08 pence to 30.27 pence per therm.
With (Other OTC: WWTH - news) supply flows forecast to be about 277.9 million cubic metres (mcm) and demand expected to be 267.2 mcm, Britain's gas system was 10.7 mcm oversupplied, National Grid (LSE: NG.L - news) data showed.
Imports from Norway via the Langeled pipeline rose to about 60 mcm/day on Wednesday, compared to around 53 mcm on Monday.
Higher wind power output softened demand for gas on Tuesday from combined cycle gas turbine plants and heating demand was lower.
Further out on the curve, the Winter '16 contract inched up by 0.04 pence to 33.75 pence per therm.
In the Netherlands, day-ahead gas at the TTF hub fell by 0.12 euros to 12.63 euros per megawatt-hour.
In Europe's carbon market, the front-year EU Allowance price was steady at 5.01 euros a tonne. (Reporting by Simon Falush)