They began showing up in the spring — e-mails, calls and unannounced visits to Dakota County office buildings from solar garden developers wanting to talk about regulations.

These gardens aren't about plants. Instead, they feature solar panels that can gather energy for use throughout a community, lowering the energy bills of those who might not be able to put the panels on their own homes and businesses.

But such "gardens" can be sprawling and unsightly, with rows of photovoltaic panels spanning the equivalent of two square city blocks. And the question of whether acres of solar panels should be allowed in shore land and sensitive flood plains has local officials scratching their heads.

"Counties haven't had time to absorb this," said Brian Ross, who works on solar energy policies for the Great Plains Institute. "They have a developer who's beating on their door saying let me in, and they don't always know who to believe."

Companies looking to install the panels face a time crunch. They need to get the systems up and in service by the end of 2016 to get a 30 percent federal tax credit, though solar industry members hope to negotiate an extension.

Some communities are responding with temporary moratoriums on the projects, to give them time to study and figure out how they fit into land use regulations.

"Developers are kind of all in a hurry," Ross said. "So when someone puts a moratorium up they're going, 'Oh geez, what does this mean?' "

Dakota County is one of the latest communities to prohibit the solar gardens, though just in certain areas. The County Board voted last week for a yearlong moratorium on the projects in townships' shore land and flood plains while they devise rules to protect the environment and residents.

Solar developers are tracking that decision.

Dakota County is a key location, said Kaya Tarhan, co-founder of SolarStone, a solar development company. It has a lot of farmland and open space but touches Hennepin and Ramsey counties, where so many energy consumers live.

Developers have applied to build 157 solar gardens in Dakota County, second only to Wright County with 177, according to Xcel Energy data. So far, 1,198 proposals have been submitted since December. One has been approved. Ross estimated at least half the proposals will fall through due to lost funding or because they do not comply with limits on the number of gardens that can be clustered in one area.

A 400-acre solar project proposed in the township just outside Monticello in Wright County has been forced to scale back under the size limits approved in June. Monticello opposed the project, which would have been located right where the city is planning a growth corridor with utilities and roadways, City Administrator Jeff O'Neill said.

"This isn't a case of not wanting it in our backyard," he said. "But we don't want it in our front hallway."

Most municipalities and townships think solar is fine, they just don't want the gardens to cause long-term problems, he said.

"The pace and the thoughtfulness that we use to deploy these systems is very important," O'Neill said. "We shouldn't be rushing to meet a federal tax credit program for developers."

Solar projects have become a top issue for townships with farmland, said Commissioner Mike Slavik, who represents much of rural Dakota County.

Slavik said communities are still struggling with the side effects of a 2013 state law that increased requirements on the amount of solar power Minnesota utilities generate. Changes to the law that year also expanded incentives and ways for people to generate solar energy, like the solar gardens program. Slavik said the changes left local governments trying to figure out zoning and other issues.

A flood of concerns

Dakota County's temporary moratorium on solar gardens in shore land and flood plains applies to 2,670 acres — just 1 percent of its township acreage, Water Resources Supervisor Tom Berry said.

But those slivers of land along waterways can be good locations for farmers looking to sell or lease their land to solar developers. Farmers want the solar systems on their least productive land, and the wet soil in flood plains and shore land areas is not ideal for crops, Berry said.

Solar arrays in shore land was one of the hotly debated issues in Wright County, which recently passed an amendment allowing commercial solar arrays, Zoning Administrator Sean Riley said. The county will require erosion control and stormwater management with projects in those areas, according to documents.

Officials didn't add solar panels as a permitted use in flood plains, he said, and developers would likely avoid building there anyway. They do not want their arrays to short out and would have to prove the system would not impede a flood, Riley said.

Dakota County officials are concerned that if solar panels and poles are placed right along rivers and streams, debris could get hung up on the equipment and prevent water from flowing, causing more flooding upstream, Berry said. Solar equipment could also get washed away.

Solar industry members, like cities and townships, don't want to rush development and end up with such unintended consequences, said Lynn Hinkle, policy director for Minnesota Solar Energy Industries Association.

"A lot of this is new territory," Hinkle said. "We're learning as we build solar arrays in different terrains and different situations what are the possible problems or benefits they generate."