MINNEAPOLIS (Reuters) - A nearly three-week Minnesota government shutdown in July over a budget impasse left broad public frustration, but little impact on state finances, the state's budget office said on Tuesday.

The longest and most expansive state government shutdown in Minnesota history left 19,000 government employees sitting at home and shuttered road construction projects, state parks, highway rest stops, the state lottery and horse racing tracks.

Costs for lost revenue from compliance with taxes, the lottery, the state parks and preparation leading up to the shutdown totaled about $60 million, but Minnesota also saved about $65 million in compensation not paid to state workers.

The Minnesota Management and Budget Department said that about 80 percent of state spending continued after Democratic Governor Mark Dayton and Republican legislative leaders failed to reach a budget deal by the start of fiscal 2012 on July 1.

The report did not quantify the indirect impact on state government from the shutdown or the private sector impact from delays in road construction projects or state permits.

The agreement that ended the budget impasse between Dayton, Republican House Speaker Kurt Zellers and Senate Majority Leader Amy Koch delayed some payments and authorized borrowing against future revenue.

The failure to adopt spending cuts or raise taxes to close long-term budget imbalances in Minnesota, along with political and social tensions between the political parties, has prompted credit ratings downgrades by the major ratings services.

(Reporting by David Bailey; Editing by Cynthia Johnston)