The Ward of Treharris is the most southerly ward in the Merthyr. The resident population of Treharris, as measured in the 2001 Census, was 6252, compared to 6090 in 1991. This equates to an increase of 2.7% in the total population of the Treharris ward. This population lives in approximately 2471 households. Of this total 48% were male and 52% were female. The ward of Treharris includes Treharris Town itself, Quakers Yard, and Edwardsville.

Treharris is one of only two areas in the Borough where the population of the ward is increasing.

Treharris is probably best known for its once thriving coal industry, and in particular the Deep Navigation Colliery. The colliery was o riginally named Harris's Navigation after the Harris Navigation Steam Coal Company's main shareholder. He also gave his name to the village "Treharris".

By 1945 there were 1,826 men working down the pit, and by the 1980’s its average output was 375,000 tons per year. The mine closures throughout the 80’s and 90’s however forced the pit to close on Good Friday 1991.

The Taf Bargoed valley comprised of 3 collieries, Deep Navigation, Taff Merthyr and Trelewis, all of which had closed by 1993. 2000 jobs were lost as a result and an estimated £6 million lost from the local economy. Local research found that the average household income fell to one third of what they were before the pits closed.

With the contraction of the local economy a steady decline of the Town Centre of Treharris followed with the closure of Shops, Local Services, Banks and Offices.

Treharris today paints a very different picture to that during the late 1980’s. The Parc Taf Bargoed, a multi million pound development situated on the site of the former pit provides a beautiful tranquil area with soothing lakes and idyllic walks to be enjoyed by both the young and the old.

Many of the derelict and run down buildings have been earmarked for future development, and the Welsh Assembly have given the area priority by allocating Communities First funding to the area. Whilst there is a long way to go to get the centre of Treharris back to the busy thriving area it once was, progress is being made, and with the community all pulling together we can breath life back into the area.

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