After descending through the rapids of the Fraser Canyon, the Fraser River emerges almost at sea level at Yale, over 100 km inland. Although the canyon in geographic terms is defined at ending at Yale, Hope is generally to be considered the southern end of the canyon, partly because of the change in the character of the highway from that point , and perhaps also because it is at Hope that the first floodplains typifying the course of the Lower Fraser are found. Downstream from Hope, the river and adjoining floodplains widen considerably in the area of Rosedale, Chilliwack and Agassiz, which is considered the head of the Fraser Delta. From there the river passes through some of the most fertile agricultural land in British Columbia—as well as the heart of the Greater Vancouver region—on its way through the valley to its mouth at Georgia Strait.
During the last ice age, the area that would become the Fraser Valley was covered by a sheet of ice, walled in by the surrounding mountains. As the ice receded, land that had been covered by glaciers became covered by water instead, then slowly rose above the water, forming the basin that exists today. The valley is the largest landform of the Lower Mainland ecoregion, with its delta considered to begin in the area of Agassiz and Chilliwack, although stretches of floodplain flank the mountainsides between there and Hope.
Several of the Fraser's lower tributaries have floodplains of their own, shared in common with the Fraser freshet. Of varying size these include the Harrison River, Chilliwack River (Vedder River), Hatzic Creek and Hatzic Lake, the Stave, Alouette, Pitt and Coquitlam Rivers. Also incorporated in the Fraser delta region are the Nicomekl and Serpentine River floodplains and the Sumas River drainage, which flow to saltwater independently of the Fraser but help drain its lowland. The Fraser is tidal as far upstream as the town of Mission, which is at the Fraser's closest approach to the international boundary, about 6 miles north of Sumas, Washington. Pitt Lake, one of the Fraser's last tributaries and among its largest, is so low in elevation, despite its mountain setting, that it is one of the largest tidal freshwater lakes in the world .
Oxbow lakes and side-sloughs are a common feature of the Lower Fraser's geography. The two main oxbows are those of Hatzic Lake and the Stave River on opposite sides of Mission, although that of the Stave has been silted in and part of it drained for a man-made lake. Around Fort Langley is an oxbow formation, mostly swamped in at the time of the fort's foundation, which was drained and made part of the fort's farm and remains farmland today. The system of sloughs and side-channels of the river is complicated, but important sloughs include those around Nicomen Island, Sea Bird Island and flanking the river from Rosedale to Sumas Mountain, on the western side of Chilliwack.
In the nineteenth century, steamboats plied the waters between Georgia Strait and Yale, and were especially busy during the gold rush of the 1850s and 1860s. Boats continued to provide a vital link in the valley as the gold rush tapered off and Europeans began farming.
Eventually, roads and railways were built, fueled by and in turn fuelling population growth. Today, the most important transportation links through the region are the Canadian Pacific Railway and Canadian National Railway transcontinental main lines, the Lougheed Highway (Hwy 7), and the Trans-Canada Highway (Hwy 1).
Agricultural land in the valley – much of it protected by the Agricultural Land Reserve – is intensively farmed: the Fraser Valley brings in over half of British Columbia's annual agricultural revenue, although it makes up a small percentage of the province's total land area.
Air quality in the Fraser Valley now exceeds the Canada-Wide Standard (CWS) for ozone (at Hope) and is close to exceeding the CWS for Particulate Matter.
The term "Central Fraser Valley" refers to Mission and Abbotsford and is included within the Lower Fraser Valley. The Upper Fraser Valley means from Chilliwack and Agassiz to Hope. The phrases "Fraser Valley towns" and "Fraser River municipalities" include Delta and Richmond, though the colloquial "in the Valley" means from Surrey and Coquitlam eastwards.
Diversity, distribution and phenology of Lygus species (Hemiptera: Miridae) in relation to vegetable greenhouses in the lower Fraser Valley, British Columbia, and southwestern Ontario
Dec 01, 2003; ABSTRACT Lygus spp. were collected from near and inside vegetable greenhouses during three years in the lower Fraser Valley,...
Pacific Fisheries Resource Conservation Council/ Communique: Resolving Agriculture Conflicts in Fraser Valley Essential to Protect Salmon Says New Report
Jun 13, 2005; VANCOUVER, BRITISH COLUMBIACCNMatthews - June 13, 2005) - Pacific Fisheries Resource Conservation Council - Tax incentives,...