Delaware County has started the formal process to acquire 213 acres owned by the Archdiocese of Philadelphia and a developer in Marple Township to create the county’s largest park.

County Solicitor William F. Martin began eminent domain proceedings Thursday by filing a Declaration of Taking for the two parcels in the Court of Common Pleas.

The County Council had already approved the measure to gain control of the mostly forested acres known as the Don Guanella tract. Eminent domain will allow the county to take the properties in return for their fair market value with the ultimate price to be negotiated with the owners.

» READ MORE: Delco plans to take land from Archdiocese to create county’s largest park

The developers would be allowed to make an appeal on the value, which would then be determined in court. Currently, the total assessed value for both properties is $31.6 million, but the negotiated price could be much different. The county did not file an estimated value in the court documents.

County officials have said the measure was needed to preserve the land from development with the ultimate goal of providing much needed open space for residents. It will also help with environmental issues, such as preserving trees for climate change mitigation, storm water management, and protection for two streams that flow into Darby Creek.

At issue is a combined tract equivalent in size to 161 football fields that has been mired in controversy since 2014 when plans were first submitted to develop it for housing and retail. Marple residents pushed back and helped thwart the first proposal.

A more recent deal from 2017 involving the archdiocese and Marple Glen LLC, owned by Carlino Commercial Development, would have created housing, retail, and institutional space. But the Marple Township Board of Commissioners rejected the proposal this year, leaving an opening for the county to step in.

The archdiocese owns 124 acres off Sproul Road that contains the shuttered Don Guanella Village, formerly a home for men with developmental disabilities, and bordering Cardinal O’Hara High School, which would not be affected by the proceedings.

A representative for the archdiocese could not immediately be reached for comment.

Separately, Marple Glen Developers owns 89 acres and has an agreement of sale on the land with the archdiocese.