Neb. Rev. Stat. § 13-927

(1) A political subdivision shall post and maintain a sign at each skatepark and bicycle motocross park sponsored by the political subdivision containing the following warning notice: Under Nebraska law, a political subdivision is not liable for an injury to or the death of a participant in recreational activities resulting from the inherent risks of the recreational activities pursuant to section 13-910 . (2) The absence of a sign shall not give rise to liability on the part of the political subdivision.