He was surprised to learn that diversions from mountain rivers swell the amount of water in the Waikato River by 25 per cent. After leaving Lake Taupo those waters go through eight stations generating electricity.
In Wanganui the councillors visited the Matarawa detention dam, one of six storing water during floods and releasing it slowly down the Matarawa Stream.
Councillors toured stopbanks providing flood protection, and visited Wanganui's ailing wastewater treatment plant. "What happened there was a most unfortunate disaster, but what's going on really has to be done."
The contrast with how well the Hunterville wastewater treatment plant worked "made us all feel rather sad about the state of Wanganui", he said.
The spread of old man's beard ( Clematis vitalba) was a really tough problem.
"It's spreading still and we don't have an acceptable level of control for it."
Despite the problems, Mr Pearce expects to enjoy his time on the council. "There was some resistance to Horizons' management systems.
"There's a very strong mood to bring all those situations into a more user-friendly kind of business and to work towards making them as cost-effective as possible.
"That could improve the commercial viability of all the area. It's very, very exciting and very important."
Mr Rollinson said he was pleased to be able to show his fellow councillors the crop rotation system used by Ruapehu vegetable growers. Like Mr Pearce he's expecting a positive time at the council, with mutual respect and good outcomes.
Mr Cotton said his first four weeks as a councillor had been a hectic whirl of paper and emails, with seven meetings in Palmerston North. "I think I'm reasonably good at time management, but it's even pushed me in the last month."
He's starting to get a grip on all the jargon, and thinks the biggest challenge is understanding "what they call best practice".
"I would say what you've got to learn is what's good practice and what's affordable, because best practice isn't always affordable."
One example was the Hunterville wastewater treatment plant.
It worked extremely well but cost $1.2 million and there were only 450 ratepayers in the area.
Mr Cotton is enjoying the challenge, and said he and Mr Pearce worked well together.
A councillor tour of the southern part of the Horizons region, the Tararua, Palmerston North and Horowhenua districts, is planned for next year.