Three people have filed appeals, county officials said Tuesday. Property owners have 30 days from the date they receive their bill to appeal.
The county has set up a call center and an email address to take questions about the fee. Payments are due in September.
Gardina said businesses in the county can get credits for steps they have taken to manage stormwater runoff.
Gates said he does not want to pass the fee on to his tenants, who run small companies.
"I'm not renting to Walmarts and JCPenneys, where it's just a drop in the bucket," Gates said. "A hit like that will take [small companies] right out."
Harford County recently mailed out its stormwater bills as part of property tax notices.
Baltimore residents can expect to receive their stormwater fee bills in September and October.
Anne Arundel County officials are preparing to mail out the property tax bills, said Tracie Reynolds, a county spokeswoman.
Howard County has not yet mailed the bills and is considering changes to a fee structure approved by the County Council in the spring.
Baltimore Sun reporters Pamela Wood and Yvonne Wenger contributed to this article.