Trees are falling at Riverside Cemetery in Denver, damaging headstones and a mausoleum's roof.For years, the cemetery used water from the South Platte River to keep the grass green. That stopped when it was discovered the cemetery had no water rights.The cemetery endowment doesn't have enough to pay for water, so watering stopped in 2003. Since then, trees have dried out and started to fall over.Fairmount Cemetery Company has owned and operated Riverside Cemetery since 1900. Fairmount and a private group, Friends of Historic Riverside Cemetery are surveying the trees to decide which should be removed.Riverside Cemetery was founded in 1876, it is Denvers oldest operating cemetery and is designated as a National Historic District. Some of the notable people buried at Riverside include Augusta Tabor, Barney and Julia Ford and all four territorial Colorado governors John Evans, A. Cameron Hunt, Samuel H. Elbert, and John L. Routt.