How New York City Really Works

NOVA PBS, tomorrow, 8-9 p.m. (check local listings). `The Hidden City': documentary on New York City. Narrated by Judd Hirsch. Produced by WGBH, Boston. POWER, water, sewage, trash. To kick off its 17th season, PBS's weekly science documentary series, NOVA, takes viewers on four tours of New York City, focusing on these subjects.

Venturing through windows, hatches, tunnels, and manholes, the camera and the narrator, Judd Hirsch, do what TV does best: give viewers new eyes and insights into the world behind (and in this case, under) the world they live in.

`The Hidden City'' is both a visual and statistical feast: enough water mains to reach China, enough daily trash to fill the Empire State Building, enough daily sewage to fill Yankee Stadium 10 times. Such facts come fast and furious, and so do the images. To keep its civilian, Everyman touch, actor Hirsch (TV's ``Taxi,'' ``Dear John'') starts with simple questions: ``What's on the other side of this electric plug?'' ``Where does this tap water come from?'' He then leads viewers into a subterranean world that is far more complicated and organized than one might imagine.

To liven the mix, Mr. Hirsch interviews key officials in each realm. For the viewer, the result is a heightened respect for services that people take for granted. One comes away with both increased concerns and refreshing reassurances that 7 million closely packed humans can coexist within four smoothly running infrastructures.

One of the increased concerns is trash. The average New Yorker's output is six pounds per day, about twice the average European. When Fresh Kills landfill is full by the year 2000, New Yorker's have a real problem. Pros and cons of various solutions are discussed in some detail.

One source of reassurance is the extremely detailed look at New York's electrical power production facilities - and the computer-controlled grid that analyzes and adjusts supply. A brief discussion of the blackout of July 14, 1977, and the consequent redesign of the system seems to prove such a blackout will not happen again.

Fortunately, ``Hidden City'' also offers some historical perspective. Centuries of efforts to bring Manhattan its huge quota of daily water have culminated in two giant tunnels, built between 1910 and 1936. City faucets now draw from 12 reservoirs spread over a watershed the size of Delaware. NOVA visits a third tunnel, eventually to stretch 60 miles, now being built 800 feet underground.

The program ends with a visit to New York's new North River Sewage plant, which is bigger than the Pentagon, and a look at trash collection problems.