HOUSTON --The first bills for Houston's new drainage fee come out next month, and for some it could be a costly one. We looked over hundreds of bills and found stark inconsistencies. We take a look at buildings that are exempt from the fees and some of the results will surprise you. It never stops at the West Houston Area Ministries. "We are very, very busy," said Shirley Downing with West Houston Area Ministries. It's a successful aid group on the west side, helping hundreds of families a month. "We're in the food pantry," Downing said. There's food and job search assistance and rental aid if it's needed; but this month after the ministry pays its drainage fee, it's likely two fewer families will get help. Every family gets about $100 in aid, but the ministry's drainage fee is $210 every month. "It's going to have to take away from something, you know, because it's not in the budget," Downing said. Against Mayor Annise Parker's wishes, City Council exempted schools and churches from the fee. The ministry group hoped it would be exempt, but even though the charity is directed by a pastor's group and is called a ministry, their city appeal didn't go well. "You are not exempt and that's the end of it," Downing said. So they'll pay a lot -- $55 more a month every month than the tallest office tower in Texas. Think about that, city records show that the ministry pays more than the tallest skyscraper in town. The money funds drainage and street projects in Houston, but when we pored over nearly 500,000 bills in the city together with Texas Watchdog, we found a program drowning in confusion and inconsistencies. "The data is confusing and the initial mistakes, from the beginning, have led taxpayers to be confused," Texas Watchdog editor Trent Siebert said. Take for example this building -- It's exempt and owned by the Union Baptist Association, a church group; but it has space for rent to anyone, and some of the other tenants are oil services companies and a patent group. How can the city exempt them and not a food bank? "I don't think that's the intent of the program. The intent of the program is to have folks pay for what their impact is on the drainage system, not necessarily for what their purpose is in the community," said Tommy McClung with the City of Houston Public Works Department. Or how about the Houston Zoo? The home of the animals is exempt from the fee, but the nearby Children's Museum of Houston isn't, and nor is the Houston Museum of Natural Science or the Houston Museum of Fine Arts. Ben Taub Hospital, which is owned by the county, is exempt from the fee, but next door Memorial Hermann Hospital, owned by a non-profit, tells us they pay. Schools across the city are exempt. Private schools apparently are too. But the K-12 Village School shows up in city records owing nearly $4,000 a year. County buildings are supposed to be exempt, unless they make money. But city records show one parking lot is off the hook -- it's exempt. It's owned by the county but leased to a private company. To make everything more confusing, Harris County tells us hundreds of county buildings mistakenly got bills this month. "Did you have a responsibility to get it right before the bills were sent the first time?" we asked McClung. "I can't speak to that because I can only talk about the reality. I mean when I look at this, I don't know that we could have done much more differently than we did," he replied. The city says all this is just a growing pain from trying to implement a program this big this fast. But to the families that will go without help from West Houston Area Ministries, the city's growing pain might actually feel like a hunger pain. "We're not resigned to it. We still got people trying to back us to help us to be exempt from it," Downing said. They can keep fighting, but their city appeals, though, are exhausted. Click here to see the city's biggest payers.