Section 923.5 - Erosion Control for Logging Roads and LandingsThe following Erosion Control standards shall apply to Logging Roads and Landings:
(a) All Logging Road and Landing surfaces shall be adequately drained through the use of Logging Road and Landing surface shaping in combination with the installation of drainage structures or facilities and shall be hydrologically disconnected from Watercourses and Lakes to the extent Feasible. Guidance on methods for Hydrologic Disconnection may be found in "Board of Forestry Technical Rule Addendum Number 5: Guidance on Hydrologic Disconnection, Road Drainage, Minimization of Diversion Potential, and High Risk Crossings" (1st Edition, revised 04/21/15), hereby incorporated by reference.(b) Drainage Facilities and structures shall be installed along all Logging Roads and all Landings that are used for Timber Operations in sufficient number to minimize soil erosion and sediment transport and to prevent Significant Sediment Discharge.(c) Ditch Drains, associated necessary protective structures, and other features associated with the Ditch Drain shall: (1) Be adequately sized to convey runoff.(2) Minimize erosion of Logging Road and Landing surfaces.(3) Avoid discharge onto unprotected Fill.(4) Discharge to erosion resistant material.(5) Minimize potential adverse impacts to slope stability.(d) Waterbreaks and Rolling Dips installed across Logging Roads and Landings shall be of sufficient size and number and be located to avoid collecting and discharging concentrated runoff onto Fills, erodible soils, Unstable Areas, and Connected Headwall Swales.(e) Where Logging Roads or Landings do not have permanent and adequate drainage, and where Waterbreaks are to be used to control surface runoff, the Waterbreaks shall be cut diagonally a minimum of six inches into the firm roadbed and shall have a continuous firm embankment of at least six inches in height immediately adjacent to the lower edge of the Waterbreak cut. On Logging Roads that have firmly compacted surfaces, Waterbreaks may be installed by hand methods and need not provide the additional six-inch embankment provided the Waterbreak ditch is constructed so that it is at least six inches deep and six inches wide on the bottom and provided there is ample evidence based on slope, material, amount of rainfall, and period of use that the Waterbreaks so constructed will be effective in diverting water flow from the Logging Road surface without the embankment.(f) Distances between Waterbreaks shall not exceed the following standards and consider Erosion Hazard Rating and road gradient: MAXIMUM DISTANCE BETWEEN WATERBREAKS |
| Estimated | Logging Road Gradient in Percent |
| Hazard Rating | 10 or less | 11-15 | >25 |
| Feet | Feet | Feet |
| Extreme | 100 | 75 | 50 |
| High | 150 | 100 | 75 |
| Moderate | 200 | 150 | 100 |
| Low | 300 | 200 | 150 |
(g) Where Outsloping and Rolling Dips are used to control surface runoff, the dip in the Logging Road grade shall be sufficient to capture runoff from the Logging Road surface. The steepness of cross-slope gradient in conjunction with the Logging Road or Landing gradient and the estimated soil Erosion Hazard Rating shall be used to determine the Rolling Dip spacing in order to minimize soil erosion and sediment transport and to prevent Significant Sediment Discharge. Guidance on Rolling Dip spacing may be found in "Board of Forestry Technical Rule Addendum Number 5: Guidance on Hydrologic Disconnection, Road Drainage, Minimization of Diversion Potential, and High Risk Crossings" (1st Edition, revised 04/21/15), hereby incorporated by reference.(h) Drainage Facilities and structures shall discharge into vegetation, Woody Debris, or rock wherever possible. Where erosion-resistant material is not present, Slash, rock, or other energy dissipating material shall be installed below the drainage facility or drainage structure outlet as necessary to minimize soil erosion and sediment transport and to prevent Significant Sediment Discharge. Guidance on Energy Dissipaters for drainage structures may be found in "Board of Forestry Technical Rule Addendum Number 5: Guidance on Hydrologic Disconnection, Road Drainage, Minimization of Diversion Potential, and High Risk Crossings" (1st Edition, revised 04/21/15), hereby incorporated by reference.(i) Where Logging Road and Landing surfaces, Road Approaches, inside ditches and drainage structures cannot be hydrologically disconnected, and where there is existing or the potential for Significant Sediment Discharge, necessary and Feasible treatments to prevent the discharge shall be described in the Plan.(j) All Logging Roads and Landings used for Timber Operations shall have adequate drainage upon completion of use for the year or by October 15, whichever is earlier. An exception is that Drainage Facilities and drainage structures do not need to be constructed on Logging Roads and Landings in use during the Extended Wet Weather Period provided that all such Drainage Facilities and drainage structures are installed prior to the start of rain that generates overland flow.(k) Where Logging Road or Landing construction or reconstruction takes place during the Extended Wet Weather Period, Drainage Facilities and drainage structures shall be installed concurrent with construction or reconstruction operations.(l) Bare soil on Logging Road or Landing cuts, Fills, transported spoils, or Sidecast that is created or exposed by Timber Operations shall be stabilized to the extent necessary to minimize soil erosion and sediment transport and to prevent Significant Sediment Discharge. Sites to be stabilized include, but are not limited to: (1) Sidecast or Fill exceeding 20 feet in slope distance from the outside edge of a Logging Road or a Landing that has access to a Watercourse or Lake.(2) Cut and Fills associated with approaches to Logging Road Watercourse crossings of Class I or II waters or Class III waters where an ELZ, EEZ, or a WLPZ is required.(3) Bare areas exceeding 800 continuous square feet within a WLPZ.(m) Soil stabilization measures shall be described in the Plan pursuant to 14 CCR § 923.5 (l), and may include, but are not limited to, removal, armoring with Rip-Rap, replanting, mulching, seeding, installing commercial Erosion Control devices to manufacturer's specifications, or chemical stabilizers.(n) Where the natural ability of ground cover within a WLPZ is inadequate to protect the Beneficial Uses of water by minimizing soil erosion or by filtering sediments, the Plan shall specify protection measures to retain and improve the natural ability of the ground cover to filter sediment and minimize soil erosion.(o) Soil stabilization treatments shall be in place upon completion of operations for the year of use or prior to the Extended Wet Weather Period, whichever comes first. An exception is that bare areas created during the Extended Wet Weather Period shall be treated prior to the start of rain that generates overland flow, or within 10 days of the creation of the bare area(s), whichever is sooner, or as agreed to by the Director.(p) Overhanging or unstable Concentrations of Slash, Woody Debris or soil along the downslope edge or face of Landings shall be removed or stabilized when it is located on slopes greater than 65%, within 100 feet of the boundary of a WLPZ on slopes greater than 50% that drain toward the zoned Watercourse or Lake, or when it may result in Significant Sediment Discharge. Removed materials shall not be placed at disposal sites that could result in a Significant Sediment Discharge.(q) In Watersheds with Listed Anadromous Salmonids and in Planning Watersheds immediately upstream of, and contiguous to, any watershed with listed anadromous salmonids, the following shall apply: (1) Constructed and Reconstructed Logging Roads shall be outsloped where Feasible and drained with Waterbreaks or Rolling Dips.(2) In addition to the provisions listed under 14 CCR § 923.2(d)(2), all permanent and seasonal Logging Roads with a grade of 15% or greater that extend 500 continuous feet or more shall have specific Erosion Control measures stated in the Plan.(3) Within the WLPZ, and within any ELZ or EEZ designated for Watercourse or Lake protection, treatments to stabilize soils, minimize soil erosion, and prevent Significant Sediment Discharge shall be described in the Plan as follows: (A) In addition to the requirements of subsections (l)-(o), soil stabilization is required for the following areas: 1. Areas exceeding 100 continuous square feet where Timber Operations have exposed bare soil, and2. Disturbed Logging Road and Landing cut banks and Fills, and3. Any other area of disturbed soil that threatens to cause Significant Sediment Discharge.(B) Where straw mulch is used, the minimum straw coverage shall be 90%, and any treated area that has been reused or has less than 90% Surface Cover shall be treated again by the end of Timber Operations.(C) Where Slash mulch is applied, a minimum of 75% of the area shall be covered by Slash in contact with the ground.(D) For areas disturbed outside of the Extended Wet Weather Period, treatment shall be completed prior to the start of any rain that causes overland flow across or along the disturbed surface that could result in Significant Sediment Discharge.(E) For areas disturbed during the Extended Wet Weather Period, treatment shall be completed prior to any day for which a chance of rain of 30% or greater is forecast by the National Weather Service or within 10 days of disturbance, whichever is earlier.(F) Where the natural ability of ground cover is inadequate to protect the Beneficial Uses of water by minimizing soil erosion or by filtering sediments within any ELZ or EEZ designated for Watercourse or Lake protection, the Plan shall specify protection measures to retain and improve the natural ability of the ground cover to filter sediment and minimize soil erosion.Cal. Code Regs. Tit. 14, § 923.5
1. Deletion of former subsection (a); addition of new subsections (a), (b), (f)(5) and (i); amendment of subsections (f)(1), (f)(3), (f)(4), (h) and (i); and renumbering filed 2-11-91; operative 3-13-91 (Register 91, No. 14).
2. Amendment of subsection (b) and NOTE filed 11-26-97; operative 1-1-98 pursuant to Public Resources Code section 4554.5 (Register 97, No. 48).
3. Amendment of subsection (e) filed 11-19-2010; operative 1-1-2011 pursuant to Public Resources Code section 4554.5(a) (Register 2010, No. 47).
4. Amendment of section heading, repealer and new section and amendment of NOTE filed 6-11-2014; operative 1-1-2015 pursuant to Public Resources Code section 4554.5 (Register 2014, No. 24).
5. Change without regulatory effect amending subsections (a), (g) and (h) filed 11-26-2014 pursuant to section 100, title 1, California Code of Regulations (Register 2014, No. 48).
6. Amendment of subsections (a), (g) and (h) and amendment of NOTE filed 6-2-2017; operative 1-1-2018 pursuant to Public Resources Code section 4554.5(a) (Register 2017, No. 22).
7. Change without regulatory effect amending section filed 10-31-2017 pursuant to section 100, title 1, California Code of Regulations (Register 2017, No. 44). Note: Authority cited: Sections 4551, 4551.5, 4553, 4561.7 and 4562.9, Public Resources Code. Reference: Sections 4512, 4513, 4551, 4551.5, 4562.5, 4562.7 and 4597, Public Resources Code; 33 USC 1288(b); and Natural Resources Defense Council, Inc. v. Arcata Natl. Corp. (1976) 59 Cal.App.3d 959, 131 Cal. Rptr. 172.
1. Deletion of former subsection (a); addition of new subsections (a), (b), (f)(5) and (i); amendment of subsections (f)(1), (f)(3), (f)(4), (h) and (i); and renumbering filed 2-11-91; operative 3-13-91 (Register 91, No. 14).
2. Amendment of subsection (b) and Note filed 11-26-97; operative 1-1-98 pursuant to Public Resources Code section 4554.5 (Register 97, No. 48).
3. Amendment of subsection (e) filed 11-19-2010; operative 1-1-2011 pursuant to Public Resources Code section 4554.5(a) (Register 2010, No. 47).
4. Amendment of section heading, repealer and new section and amendment of Note filed 6-11-2014; operative 1-1-2015 pursuant to Public Resources Code section 4554.5 (Register 2014, No. 24).
5. Change without regulatory effect amending subsections (a), (g) and (h) filed 11-26-2014 pursuant to section 100, title 1, California Code of Regulations (Register 2014, No. 48).
6. Amendment of subsections (a), (g) and (h) and amendment of Note filed 6-2-2017; operative 1/1/2018 pursuant to Public Resources Code section 4554.5(a) (Register 2017, No. 22).
7. Change without regulatory effect amending section filed 10-31-2017 pursuant to section 100, title 1, California Code of Regulations (Register 2017, No. 44).