After a serious injury I have been told that my case was pointless because of the cap on rec. centers and other city properties what should I do next?

As you have already been informed, the cap in Colorado for damages in a tort claim against the state is $150,000.  As a practical matter, most personal injury lawyers will handle a case for a fee of one-third of the cap so you should consider why lawyers have refused your case.   As to your question, you certainly can file the claim on your own but first you must satisfy the requirements for filing a suit against the state.  These are provided in the Governmental Immunity Act (GIA) which requires  notice to be given to the alleged defendants and their counsel. The relevant GIA notice provision states that: Any person claiming to have suffered an injury by a public entity or by an employee thereof while in the course of such employment shall file a written notice as provided in this section within one hundred and eighty days after the date of the discovery of the injury, regardless of whether the person then knew all of the elements of a claim or of a cause of action for such injury. Compliance with the provisions of this section shall be a jurisdictional prerequisite to any action brought under the provisions of this article, and failure of compliance shall forever bar any such action. Section 24-10-109(1), C.R.S. (l988 Repl. Vol. 10A) The subsequent sections provide the details for adequate notice.  Please note that you must give this notice within 180 days of your accident or you are barred from filing a lawsuit.  Good luck.