Rock Creek Retrofit Project

Turbine I Setting


This Web page provides background WORKING materials for designing the Rock Creek Retrofit Project hydropower turbine number I.  The setting is in Northern California approximately 125 miles NNE of Sacramento on the north fork of the Pit River.  The Rock Creek Diversion Dam is owned and operated by PG&E.  Turbine I setting site inside the central pier of the existing dam and supplies part of the fish release water to the river.  Turbine II is on the Right wing wall and is not discussed in this section.  Required fish release flow volumes are in excess of what we will use in this design.  The dam is operated as part of FERC Project 1962 and following the release stipulations in the Rock Creek Cresta Settlement Agreement available here.


Physical Site


The following documents provide a description of the Rock Creek Turbine I setting.


·        Setting Discussion (HTML)


·        Internal Dam Pictures (JPEGs)


·        RC-T-3 Setting Drawing - Empty 11x17” (PDF).

·        RC-T-5 Design Intent and Setting Schematic Sketch (8.5” x 11” PDF)

The following three drawings show Francis Turbines in slightly diffierent settings at about the same place.

Flow & Head Estimation


Included is an estimated Head/Flow curve.  This should be used as a first cut in turbine selection.  Most additional material supplied in this section is to support this curve and to provide setting information as the site is severely space constrained.  Supporting analysis is included in the following documents:


§        Power Analysis spreadsheet – includes all assumptions for the head/flow graph. This is Microsoft Excel. It must again emphasized that these papers are working papers and are being shared as working documents for discussion.

§        Pipeline pressure loss curve. This curve is for new pipe; a 17 % increase is added for age in the ensuing spreadsheet.



Photographs of the site are available here.  

Also useful are spring 2004, setting review drawings showing some discussion turbine configurations.  These drawings, {RC–3} and {RC-4}, are illustrative only but very close to best plans under consideration.  These drawings should be printed at 11x17” for the scale rules to be accurate.  Vertical turbine-pump-as-turbine arrangement is not shown, but may be advantageous in that the vertical generator can be fit directly over a vertical fixed geometry propeller turbine at the bottom of the 5’ by 8’ shaft taking advantage of the vertical space available.


Also is a set of review drawings discussed with agencies and interested people in the spring of 2004.  This document contains a 1985 PG&E proposal for a turbine in the same position as is being applied for here.  This file is about 6 megabytes in size will take several minutes to download. The PG&E design used the water through the now abandon, and buried, lower conduits.


Additional background documents include:


§        The Plan, Elevation, and Section drawings in the Rock Creek Preliminary Permit section.

( These were distributed to an extended service list and are available from the FERC. )


§        Interconnection Site Plan: {RC – E – 2} (available in the Set of Zipped Interconnection files here)

(These have formed the basis of discussions with PG&E)


§        Further detailed elevation data are given in an Excel Sheet. This sheet is included as background data only to tie elevations between different PG&E drawings as different elevation data are used.