Northampton, a town of 29,000 people in Western Massachusetts, is home to a Coca-Cola plant that churns out several of Coke’s fruit juice lines. And that plant is also churning out wastewater that is becoming to expensive for Northampton’s wastewater treatment facility to process. Rising costs and the possibility of tensions increasing between a city and one of its largest employers is an example of how municipalities end up fronting and subsidizing the costs of a large company’s operations.