By the 1920s, however, the increasing use of combustion engines and availability of power from electrical utilities had outmoded the use of water power, much of the original reason for locating the new urban industrial life in the valleys. Now coal and oil could be used to supply a steady source of power to turn the wheels of industry rather than depending on the uneven flow of a river that changed with every storm and season. A new phase in the land-use history of the Uplands had begun. Like agriculture before it, industry started slowly abandoning the rugged terrain of the Uplands. Now, just as the stone walls of abandoned colonial farms run through the woods, forgotten factories stand by the river banks. These old mill buildings were built to last, products of a more hopeful time, and strikingly handsome examples still may be seen in Baltic, Manville, Occum, Wauregan, Collinsville, and many other small valley towns.

Despite the move away from water power, some valley towns continued to grow. One reason was simply that the infrastructure transportation networks, housing for workers, and government - was already in place. But land resources also played an important role. The valleys are natural transportation corridors, and highways and railroads tended to follow them. In addition, rivers continued to be valuable for supplying drinking water to maintain an urban population, for dilution of industrial and urban wastes, and for various industrial processes requiring large volumes of water. One industry that has survived in the Uplands is brass production, still carried out in mills on the Naugatuck and Pequabuck rivers - principally in Waterbury and Bristol. The brass industry is especially dependent on a good water supply for processing and waste dilution, and it has found these Uplands rivers to be adequate sources.

The continued need of many industries for a substantial water supply, however, has not been enough to attract many new factories to the Uplands. Water can be found pretty much anywhere in Connecticut, be the land rugged or flat. (The Uplands have the edge only in the occurrence of sites suitable for water power, not in overall water supply.) And if flat land with a good water supply is available elsewhere, why put up with the much higher development costs of locating on the Uplands'

99