A review of drainage systems across Somerset has been carried out to see what improvements are needed.
The Somerset Rivers Authority-funded study looked at 20 recently built housing estates, retirement apartments and industrial units.
It was part of work to reduce flood risks across the county.
Officials say they wanted to see what's happening to any water run-off from new developments.
John Osman, Chairman of Somerset Rivers Authority, said: "This review of developers’ SuDs’ (Sustainable Urban Drainage Systems) schemes is a unique and impressive piece of work that's only happened because Somerset has the SRA.
"We've funded it because we know that people do worry about the run-off of water from new developments. So we wanted to see how SuDs are working.
"Are they being built as designed? Are they being maintained? Are developers achieving as much as they could? Those are the kind of questions we wanted to investigate.
"We've found that there are good examples of SuDS in Somerset - but there are also areas where the SRA and its partners can work with developers to try and achieve more.
"We are now aiming for improvements across Somerset.
"SuDs aspire not just to control and reduce flows of water, but to improve water quality and to make places greener and pleasanter for people and wildlife.
"This can be achieved through using natural measures such as streams, ponds and reed beds and techniques such as rainwater harvesting, permeable paving and tree-planting.
Twenty recently-built sites were inspected. These included big housing estates, retirement apartments, industrial units and offices, an arts centre, and a hotel and pub."
Councillor David Hall, Somerset County Council Cabinet member with responsibility for flood risk management, and the council’s representative on the board of the SRA, said: "This SRA-funded project has given us a huge amount of valuable evidence.
"It will help us all to achieve better ways of managing surface water in new developments.
"It will also help us to realise the full potential of wider initiatives like Taunton Garden Town.
"And it will be of interest nationally, because issues with SuDs are not confined to Somerset.
"We will all benefit from this.
"The people of Somerset will get greater protection against flooding and better places to live, work and visit, and developers will get useful and realistic guidance that helps them to build properties that people want to buy and rent. It’s a win-win."