All Wet on Wetlands

THE motives behind the current revision of the Clean Water Act surfaced unmistakably last week when the House of Representatives passed its bill despite a National Academy of Sciences (NAS) report that exposed the shakiness of one of its key provisions, wetlands protection.

''Good science,'' which gets plenty of lip service in Congress, is out the window in this bill, which was put together largely at the bidding of business and agricultural interests.

The NAS study affords no justification for the narrow definition of wetlands used in the House legislation and dismisses as impractical the ranking of such lands to determine the level of protection they deserve.

Under the House measure, up to 60 percent of the country's remaining wetlands could disappear as a result of development. That prospect may not concern those who simply want the maximum economic return from their land and have found federal clean-water regulations burdensome and unfair.

But a broader public interest is at stake in wetlands regulation, as in other environmental protection measures, and that interest is being pushed too far into the background by the current mood in the House. Wetlands filter pollutants and are essential to preserving adequate supplies of pure drinking water; they serve as overflow safety valves in flood-prone areas; and they are critical habitat for birds and other wildlife.

It's worth noting that even under the clean-water statute wetlands loss has continued, though the rate of loss has been cut in half since the law was first enacted in 1972. Still, some 260,000 acres a year have disappeared since the mid- '80s, according to the Natural Resources Defense Council. Some areas, such as the coastal marshlands of Louisiana, have been particularly hard hit.

There may be room for reassessment and fine-tuning of wetlands regulation, but there is no room for the kind of blinders approach that ignores scientific findings and opts for arbitrary limits, such as dictating that no county can have more than 20 percent of its wetlands in the so-called high-value category, which triggers the highest level of protection.

The Senate, urged on by legislators of both parties who understand the benefits of wetlands, should come up with a Clean Water Act revision worthy of the law's name.