American River Bancshares (AMRB) 8-K Departure of Directors or Certain Officers

Exhibit 99.1

September 26, 2011

Mr. David T. Taber

President and Chief Executive Officer

American River Bankshares

3100 Zinfandel Drive, Suite 450

Rancho Cordova, California 95670

Dear David,

I will retire from my position as Chief Credit Officer of American River Bankshares and American River Bank effective between March 15 and April 1, 2012. I am leaving for no other reason than that it is an opportune time for me and my family.

I joined our company more than 17 years ago, and each day since has brought rewarding work. I would like to thank you, my fellow employees, and the Board for the richness that only a family of colleagues, serving great clients well, can bring.

Sincerely,

/s/ Douglas E. Tow

Douglas E. Tow

Chief Credit Officer

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