The Snoqualmie Valley introduces itself with a roar in its spectacular 270-foot-high falls, but then winds peacefully 43 miles north through flat farmlands between fir-covered ridges. Residents, farmers, foresters and officials are working out a new land ethos here, forging a new relationship to nature as we live within it—messing with the rigid categories of pure preservation versus unrestrained urban growth. The new ethos emerging in the Snoqualmie valley is imperfect, incomplete and contentious. But as I performed research for my book, The Agile City, I found it to be one of the few places in America that genuinely engages the question of how people can gracefully live and thrive in a precious landscape.

It’s not what people started out to do. As part of the efforts of King County and Washington State to restore rapidly declining wild salmon stocks, officials have asked farmers to erect fences and maintain forested buffers as deep as 300 feet along rivers and streams. Protecting streams and spawning beds has become a huge public-works effort that may cost more than $3 billion, with some elements of recovery taking as long as 50 years.  In urbanized areas, salmon-habitat restoration has stymied a mall developer hoping to expand over a buried stream. It stopped a golf-course owner who sought irrigation water from a salmon-critical source. But a great deal of the effort – and the controversy  – is focused on the rural Snoqualmie Valley, where no more than 65 percent of the forest cover is gone, meaning the river basin can be restored to levels impossible in more urban areas.

Although the state and county are spending to naturalize river edges and remove levees so that seasonal floodwaters will flow safely into low-lying bottomland, the burdens of salmon preservation have fallen hard on farmers. The stream buffer strips can significantly reduce usable pastureland and must be managed to avoid manure pollution and erosion. As you drive the valley, you see fast-growing cottonwoods sprout from fields that once supported herds of dairy cows. The county, it seems, muse choose between farmers and salmon.

It is trying to have both. A separate effort has aggressively attempted to help farmers prosper. The Farmlink program draws young urbanites to farming, boosted by rapidly growing demand for locally produced food. And the county has drawn a growth boundary to check the spread of Issaquah and Redmond, as well as funnel limited rural growth into the valley’s towns. Drive into Duvall, a small town that had languished largely forgotten for decades, and you see its once desultory main street, Highway 203, lined with substantial new houses, apartment complexes, sidewalks and a strip center sporting an appliqué of bungalow-style criss-crossing beams.

By focusing development into compact form and paying close attention to how much land is forested (and therefore permeable to water), King County does much more than save salmon. The salmon-saving regime is an analog for the kind-of urban agility places must develop in a climate-change era, where storms and floods may become more frequent and where climate change may alter what crops will grow and what species (including salmon) will thrive. Especially as global warming has asserted its prominence, officials have integrated these efforts so that they are at less costly cross purposes and better aligned to develop multiple benefits. Agricultural flood-control measures promoted by the County, for example, include measures to protect salmon streams. A review of urban growth boundaries in four Puget Sound counties has been integrated into an action plan to meet climate-change goals.

King County has done much in the Snoqualmie Valley that advocates of rural values and lifestyle would like to see. Like so many other precious places, the valley retains a look of tradition, of wildness and authenticity. But it is a look that can only be sustained through a complex regulatory structure and a governmental engineering of the rural economy that may not prove sustainable. Even a home owner’s addition of a barn can involve hair-splitting by biologists over whether a stopped-up ditch must be deemed a wetland of potential interest to a browsing maternal salmon. The invasiveness of the regulations has led to rural residents accusing urban elected officials of dumping the greatest burdens on them. (A court case overturned the 65 percent tree-cover requirement in 2009.) For the foreseeable future, the delicate balance among fish, farming, residents’ aspirations and the pressures of urban growth can only be maintained by perpetual negotiation.

King County’s imperfect efforts show that we can adapt landscapes and live within them in a more agile way. Moving ahead, we’ll have to find ways to do more in a less onerous fashion. Yet when people say making salmon, farmers and rural residents all happy seems Pollyanish, I think back to high school. Then the valley hosted pioneering organic farmers who were generally deemed drug-addled nuts.