The letter, which is dated Oct. 18, was posted Tuesday on the official website of Susan Eisenhower, the granddaughter of the former president. The letter is addressed to Sen.
"We have priorities more urgent than building such an expensive memorial right now," wrote John Eisenhower in the letter. The estimated cost of the memorial, which was designed by Frank Gehry, is currently at above $140 million, some of which would come from federal dollars.
"While no one wants to see taxpayer money come to naught, the memorial design is very controversial and unlikely to meet its financial goals."
The family said it recommends that taxpayers and donors would be better served by the creation of an "Eisenhower Square" -- an open green space with a statue in the middle with some of the president's quotations.
The family said it believes the Eisenhower Memorial Commission isn't serious about re-examining Gehry's design, which it considers to be "too extravagant" and "off base."
Last week, the Associated Press reported that approval for the memorial design had been delayed to 2013. In recent months, Gehry has defended his conception for the memorial but has also implemented some changes to the designs.