CONSERVATIONISTS often talk about the fine line between survival and disaster for our precious wildlife and fragile environment.

One place to see this quite graphically is down at Trimley Foreshore, where a river wall path of just a few feet wide is literally the dividing line between two very different habitats – where one would destroy the other if the narrow way crumbled.

On one side of this wall is the tidal River Orwell, sucking in salt water from the sea, and on the other the fresh water of favourite fishing spot Loompit Lake.

If the river erodes or breaks through the wall, there would be disaster – the wound would allow salt water to sweep into the 34-acre lake, wrecking it.

Not only would the water be different, ruining the habitat of many plants, birds, fish and water-borne insects, it would become tidal, rushing in and out daily, creating an entirely different environment – possibly marsh or saltings – for very different species altogether.

On top of that, there would be no river wall and one of the county’s best riverside walks would be lost or only possible at low tide.

A few years back there was some criticism of landowners Trinity College, Cambridge, when it repaired this river wall with a mixture of old builders’ waste, rock and bricks.

People said it was ugly and would ruin the setting – though Trinity officials said the wall would soon be green with algae and seaweed and blend into the surroundings, which to a large extent it has.

Others said Trinity was taking the cheaper option, which it was.

But then sea walls cost tens of thousands of pounds per foot and the college was not about to splash out millions to protect a trout lake.

It’s easy though to see what would have happened if Trinity had walked away and allowed the wall to crumble and be breached.

Our environment is so fragile.

Witness what has happened to the habitat at Landguard at Felixstowe.

More than one hundred years of shingle build-up wrecked in a few months when sand dumped on beaches north of it to bolster new sea defences was eroded and swept south to cover its shores. Most of Landguard is now a mix of sand and shingle, threatening its ecology.

With money becoming increasingly tight, we will face tough battles ahead to protect our enviromnment when it comes under threat in the future from man-made or natural problems.

? Give me your views – write to richard.cornwell@eveningstar.co.uk or Your Letters, 30 Lower Brook Street, Ipswich, or email eveningstarletters@eveningstar.co.uk

? Read Richard Cornwell’s full column every week in FX – the eight-page pull-out all about the Felixstowe area in the Evening Star every Wednesday.