On Gardener's World recently Nick Bailey put a small half barrel pond into a semi shaded place in a garden to encourage wildlife. He mentioned the 'wildlife corridors' between gardens that allow creatures to travel between gardens (under or through fences) to find their own best habitats. The smallest of water areas in a garden will increase the number of insects, amphibians and birds that will visit.
He dug down into the ground (but mentioned a raised pond on a patio would also encourage certain species of wildlife and birds to visit). He made sure the pond surface was level with a spirit level and then improvised some shelves around the back edge for the aquatic plants using bricks to different levels. The front space was left clear for a dwarf waterlily.
On the brick shelves he placed tall Equisetum japonicum, flowering Iris versicolor, and Carex pendula (though we prefer Carex riparia as it is more water tolerant) and toward the front he placed Mentha cervina (available in both purple and white). In the deep section he placed Nymphaea Solfratere but Aurora is similar in colour and pink colours would be Perrys Baby Red or Laydekeri Fulgens and white, candida. The container would also need a portion of oxygenating plant - either Myriophyllum spicatum or Fontinalis antipyretica.
He blended the pond into the surrounding border area by repeating the Carex outside the water making a visual transition from pond to garden which allows amphibians a continuous emergence zone of foliage to hide in when they come and go from the water area. Also included outside the water were a Ligularia similar to dentata Desdemona with round purple tinted leaves.
It was a great TV piece showing that a project like this can be undertaken in a weekend and will help the wildlife around to visit your garden.
Every garden should have water in it and the wildlife will appreciate your efforts and visit you very quickly.