The entire Shannon catchment, extending from the river to the highest contours on either side, should be protected by an amenity designation to curtail the spread of inappropriate development, according to An Taisce.
In a submission to the Oireachtas Committee on the Shannon, the conservation body also calls for an end to attempts to drain the river to provide flood-free farmland, saying such drainage has been "wholly destructive" of wildlife habitats.
Noting that the Shannon is now classified as the sixth most polluted river catchment, with only 59 per cent of its waters remaining in the Class A category, it says the restoration of the water quality must be "a national environmental priority".
Blaming excessive use of phosphate and nitrate fertilisers and poorly-controlled factory farming as the main culprits, it calls for an end to "environmentally destructive agricultural methods" by switching subsidies to more sustainable farming practices.
Although the Shannon catchment had not suffered the level of landscape destruction now "irrevocable" in major parts of Kerry, Donegal and Galway, An Taisce's submission says a major initiative is required to avoid repeating the mistakes made in these areas.
At present, "only a small proportion of the total embanked area of the Shannon is designated as a landscape of high amenity". While most of the area around Lough Allen was designated, only a small part of the area around Lough Ree had been given similar protection.
If an overall amenity designation was adopted, as An Taisce proposes, planning applications for "one-off" (individual) houses would be refused unless the applicants could show that any proposed development positively enhanced the landscape and ecology of the area.
They would also be required to provide a "need statement" justifying the choice of site, an appraisal of the energy demands of the house, an assessment of the impact of its sewage disposal method on groundwater sources and of the number of car journeys it would generate.
Any permission should also be conditional on the siting and design complying with An Taisce/ Bord Failte's guidelines, Building Sensitively in the Irish Landscape, as well as excluding uPVC as a material, retaining hedgerows and reaching agreement on waste minimisation.
While An Taisce says it supports the maintenance of a population in rural areas, it warns that the proliferation of accumulated "ribbon development" housing is suburbanising the countryside, destroying its landscape character and creating long-term car dependency.
In this context, its submission describes the Upper Shannon Rural Renewal Scheme as "seriously ill-advised" because it was "effectively a blank cheque incentive mechanism which is linked neither to any strategic planning structure or guidelines nor to quality thresholds".
It warns of the dangers of environmental damage, such as that which occurred in seaside resorts like Courtown, Co Wexford, being replicated in the upper Shannon. (The rural renewal scheme covers all of Cos Leitrim and Longford and large parts of Cavan, Sligo and Roscommon).
An Taisce calls for the scheme to be withdrawn pending the adoption by the relevant local authorities of integrated area plans.
It also complains that the National Development Plan was being implemented without any spatial strategy. This was resulting in uncontrolled suburban sprawl and scattered urban-generated housing in the countryside, compounded by holiday homes in scenic areas.
It recommends that tourist accommodation be built in appropriately planned clusters close to existing amenities, while ensuring that the scale of holiday home housing in particular village locations did not "swamp" the character of the surrounding area.
In the Shannon estuary, An Taisce says, future industrial development should be located in areas served by rail. It also describes the ESB's coal-fired power station at Moneypoint as "the single most problematic greenhouse gas and acid-rain-producing stack in Ireland".
