Hook sizes and numbers will be restricted for the same period, baits other than artificial fly and spinner banned, and salmon net fisheries forced to delay their activities. The agency says these measures are essential if the wild fish is to survive.
But it has drawn back from the drastic ban on fishing it was considering three months ago, which was a step too far for the angling sector and the substantial tourist industry it supports.
The agency now believes that catch-and-release can protect plunging salmon stocks while allowing fishing to continue. It has the further advantage of "keeping people on the bank" - allowing bailiffs and ghillies to make sure that conservation measures are not undermined by poaching.
The restrictions being proposed today will be discussed by regional fishing interests at a series of meetings over the next few weeks and then put forward as Environment Agency by-laws, which will need ministerial approval and will probably be in place by next March.
They will bring in catch-and-release from the start of the season, which varies with different rivers but can be as early as 15 January, until midsummer: the date is still to be determined, but it will be either 1 or 16 June or 1 July.
The 536 holders of licences for salmon netting in England and Wales will also be restricted and will not be able to begin operations until June.
The measures are particularly aimed at protecting spring salmon, the larger fish that have spent several winters at sea and tend to return to their native rivers early in the year, as opposed to grilse, the smaller, one-sea-winter fish that come back later.
`Springers" have suffered most in the salmon's spectacular decline over the past five years, which has raised the spectre of its extinction as a wild river fish in Britain.
Earlier this year the Environment Agency revealed that the 1997 salmon run was so bad that the overall level of spawning was only 60 per cent of that needed to sustain the population. In many rivers, salmon runs are a fraction of what they once were: in 1972, the catches in the River Wye in Wales and the River Test in Hampshire were 7,400 and 1,052 fish respectively; last year the figures were 733 and 49.
For big fish, those of more than 70cm, which tend to weigh more than 3.7kg, catch-and- release may be insisted upon under the agency's proposals for the whole season from January to October.
Many theories have been put forward for the salmon's decline. The principal ones are global warming, with the change in oceanic climate altering the distribution of the salmon's marine food stocks; overfishing at sea by boats from Greenland and The Faeroes; and the salmon- farming industry, which has caused a rise in sea-lice to the detriment of the health of the wild fish that catch them.