SANFORD – As town officials began their review of the site plan for a proposed $650 million gambling casino and resort, sewage and water emerged as major issues.

Casino developers have hired Sebago Technics, a Westbrook engineering firm, to look at ways to mitigate the resort’s impact on the town’s sewer system and water department, as well as roads.

Walter Stinson, who heads Sebago Technics, was among the observers Thursday in the town’s opening round in the site plan review process for the casino project undertaken by the Passamaquoddy and Penobscot Indians.

Michael Hanson, head of the Sanford Regional Sewerage District, said the casino project, estimated to deliver 1.2 million gallons of sewage a day, will eat up much of the district’s excess capacity of 1.4 million gallons a day. He said if the casino ties into the district’s system, only 200,000 gallons a day will be available for future growth. He said the community must decide whether it wants to give away nearly all of its excess capacity or require the project to find alternatives to the town’s system.

Dennis Knowles, superintendent of the Sanford Water District, said the district needs more specific information about the proposed casino resort’s water use in order to determine if the district will need to have to dig more wells and install more pumping stations.

Casino developers last month delivered their initial sketch plan for the project that will include an 875-bed, six-story hotel, 60,000-square-foot convention center, eight restaurants, retail shops, theater and 18-hole golf course to be built on 362 acres of land the tribes have optioned across from the Sanford Regional Airport.

The site plan review is just one of many hurdles facing the project.

The tribes are seeking permission in a statewide referendum Nov. 4 to operate a gambling casino. The project must also pass state environmental and transportation impact reviews. The U.S. Environmental Protection Agency may also get involved, said James Gulnac, town planner.

Because of its proximity to the airport, the project must receive approval from the Federal Aviation Administration.

It also faces local reviews by the town’s site plan review committee, planning board and contract zoning process. Either town meeting members or the new seven-member Town Council must approve project.