Proceeding pursuant to CPLR article 78 to review a determination of the Commissioner of the New York State Department of Environmental Conservation, dated July 8, 2002, which, after a hearing, denied the petitioner’s application for a tidal wetlands permit to construct a private dock.
Adjudged that the determination is confirmed, the petition is denied, and the proceeding is dismissed on the merits, with costs.
It is well settled that in a proceeding pursuant to CPLR article 78, the factual determinations of the Commissioner of the New York State Department of Environmental Conservation (hereinafter the Commissioner) must be upheld if they are supported by substantial evidence (see Matter of Pell v Board of Educ., 34 NY2d 222, 230 [1974]; 300 Gramatan Ave. Assoc. v State Div. of Human Rights, 45 NY2d 176, 179 [1978]). Substantial evidence is “such relevant proof as a reasonable mind may accept as adequate to support a conclusion or ultimate fact” (300 Gramatan Ave. Assoc. v State Div. of Human Rights, supra at 180). In this case, the Commissioner’s determination that the proposed dock, *715a 186-foot-long, 1,592 square-foot structure, which had no equivalent on the adjacent shoreline, would have an undue adverse impact on tidal wetlands and was unnecessary or unreasonable under the circumstance is supported by substantial evidence (see 6 NYCRR 661.9 [b] [1] [i], [hi]).
The petitioner’s remaining contentions are without merit. Ritter, J.P., Smith, H. Miller, and Goldstein, JJ., concur.