The Theph river [θɛf] (Arithide Taphae [ta'fai]) is one of the most important rivers of Arophania, with three of the largest Arithide cities sited along its course: the old royal capital of Isphea on its delta, the historic and vibrant capital of Lazea at its confluence with the Nes river, and the southern economic centre of Aebea along its mid-course. As the Taphae-Nes river system it has the largest drainage basin and discharge volume on Arophania, and makes up one of the three Great Rivers of Arithia.
The English name is from the Dethric corruption.
The Theph starts in the slopes of the south-central Alerryagi, flowing first east then turning northwards on the Nimaean plain towards the Ordaryagi, then flowing once again eastwards along it, before merging with the Nes river at and exiting to the north through the Calagian Pass as the Taphae-Nes, emptying into the Chisthian Sea in a triangular delta.
Agriculture & fishery
The Theph has been an important source of food fish for the Areth, and remains so today. More than 30 species of edible freshwater fish are known to live along its course, including the famous Besrian. In recent times, however, concerns over water pollution midcourse as well as overfishing of certain species has put a damper on fishing, though in more rural areas recreational angling is still a common pastime.
- See also Fishes of the Theph river for more information
Besides fishing, the Theph plays a key role in the agriculture of the region, thanks to its origin in the Alerryagi, which erodes and dissolves from the mountain slopes many minerals that enrich the land downstream through which the river passes. Farms on the Nimaean plain depend heavily on the river (and, to a lesser extent, on the Nes) for irrigation as well.
Industry, commerce & transport
As the continent's largest navigable river and the site of Arithia's three largest cities, the Theph is a natural conduit for trade and transport. In the early days of Areth expansion, the river was the first, most convenient, and most common way to access the Arophanian interior. Even today, fully half of the Arithide internal trade is carried on the waters of the Theph, ranging from industrial inputs like oil and cotton from Audoria, to manufactures like automotive vehicles or even farm produce. Hovercraft commuter links have been established along the river's lower course in recent years, replacing the old passenger boats, ships and ferries that used to ply the waters.
Due to its large discharge, the Theph has been able to sustain a degree of relative cleanliness and purity of its waters despite the heavy agriculture that has been going on in its basin for thousands of years.
In the Industrial Age, however, as the nation rapidly industrialised around its cities (most of which, not coincidentally, are located on the river), the Theph became increasingly polluted due to chemicals and other toxic effluent from factories, and synthesised fertilisers from agriculture, which are much harder to break down or flush out. When improvements in technology in the modern era allowed ever more aggressively intensive cultivation of the land, especially pastoral farming, the condition of the Theph's waters rapidly deteriorated, especially as industry began to use more chemicals in manufactures, without ascertaining the environmental impact thereof.
In 1934 CIE, water quality became so abysmal that at Regea, an industrial town, the river turned a noticeably dark shade of brown, giving off a stench that came from the burgeoning bacterial population in the waters and that carried all the way downstream to Lazea. Eutrophication had caused large numbers of fish and other aquatic life to perish, and the decomposing matter did not poison only the air: in the sixth month of that year, large-scale water poisoning in many cities occurred, and economic activity almost ground to a halt as water supplies were cut, investigations were made (which eventually concluded perfunctorily), and alternative water sources were found.
The Theph was cleaned up in a large-scale civil engineering operation from 1935-1938 CIE, and environmental laws and regulations were drastically tightened, polluting industries and firms shuttered or forced to overhaul their operations, and farms likewise barred from using toxic fertiliser and forced to treat heavily chemical-laden sewage, among others in a series of stringent measures to protect the river. The damage had been done, however; marine species in the river fell from an estimated 3,600 before industrialisation to less than 600, and is still recovering: at last count, in 2001 CIE, scientists listed just 1,400 species.