some 20 million children in the u.s. will go to bed tonight without a father in the home. citing statistics is easy. fixing the problem is not. bret? bret: william, thank you. fentanyl is no longer an underground crisis but a new method of combating it has gone underground, literally, through sewers. communities around the country are exploring how sewage testing can help track where fentanyl and other substance use are surging. correspondent alexandria hoff shows us tonight. from the depths of a less than fresh scented tank, a sesnapshot of public health is collected. samples of raw sewage are pulled over 24 hours and sent to a lab for what is essentially a community drug test. instead of one person, you are testing 2500 people. untreated waste reveals where