In the 1960s and 1970s, the United States attempted to improve the image of nuclear bombs by using them for public works. This went about as poorly as you'd suspect.
It was called Operation Plowshare. Nuclear bombs were tested to see if they could excavate large caverns inside mountains, produce steam power, or clear rough terrain to make highways. The vast amount of radiation, and the fact that underground caves would stay boiling hot for months after the explosion, made excavation impracticable. When the government tried boiling underground water for steam power, they got steam, but they didn't always have a good way to channel it. Random patches of the ground nearby would explode outward, venting radioactive steam.
The Soviet Union was thinking along the same lines as the United States. They designated a nuclear testing site (without regard for nearby cities full of people, of course) and tested various aspects of nuclear bomb. They bombed the Chagan river, for example, as a way of testing whether nuclear bombs would be a good way to make reservoirs. They got a lake, all right, but it was an irradiated lake that is still not safe to swim in.
All in all, nuclear civil projects were a massive mistake. There was one use, though, that seemed to work. The Soviet Union tried it several times, and actually had some success: it turns out nuclear bombs are great ways to put out fires. That's not as unimpressive as it sounds! Underground fuel reserves are vast stores of combustible material that cannot be reached by human firefighters, but can quite merrily burn. Coal, peat, and gas fires can burn for decades. Centralia, Pennsylvania had a coal seam that caught fire in 1962 and is still burning. The Urtabulak gas field caught fire in 1963. It burned steadily for three years. In 1966, the Soviet Union decided to do something about that.
The gas fire was ventilated by the holes that had been drilled to harvest the gas; if the holes could all be sealed shut, the fire would go out. Naturally, no one could go into a vast gas fire to shovel earth into a deep hole. Geologists and physicists calculated that a nuclear explosion equal to about 30 kilotons of TNT could seal shut every hole within about 50 meters. The rock would basicallymelt over the fire. In the fall of 1966, a special nuclear bomb was detonated in one of the holes, and fire was out in 23 seconds.
But if it's not one thing, it's another. Within a few months of that fire going out, a new fire, in another gas field, erupted. In 1968, the Soviets dropped a bomb into that one. This took longer. For a few days, rock and other earth flowed into the holes, but eventually it worked. The fire went out. In 1972, another well was sealed off after it caught fire. The last known attempt at sealing a gas fire with a nuclear weapon was done in 1981, and it did not work out. The scientists couldn't get accurate data on the location of the vents in the well. The bomb went off, but the well never entirely sealed shut.
Since then, the fires have been allowed to burn and the nukes have continued to rot, quietly, in various silos across various countries.
Top image: National Nuclear Security Administration.