600-Acre Family Ranch

Level 1 – Site Assessment

Location: San Luis Obispo, CA

Project: 7th Generation Design was invited to conduct a Level 1 Site Assessment of a 600-acre property located in San Luis Obispo, CA. The landowner’s communicated a desire to live together on this family property and regenerate degraded portions of the landscape, with the following major goals:

  • To live together as a multi-generational family unit while feeling safe, secure and serene on the land.
  • Improve ability to monitor, manage and maintain the more distant portions of the property.
  • Rehabilitate the health of the soils.
  • Provide an educational space for schools and organizations to engage with nature. 
  • Inspire the community with art.
  • Improve the wildlife habitat and access throughout the property.
  • Generate more income from the land.

Existing Conditions:

  • A primary valley oriented mostly on a northwest x southeast axis (which a highway follows on the east side of the valley) and traversed along its bottom by a county road. 
  • Temperatures with typical highs between 60-85℉ and lows that only very rarely drop below freezing, with an average of 450 chilling hours (<45℉) per year.
  • Average rainfall of approximately 22 inches per year, with approximately 400 million gallons of water landing on the property per average rain year. Abundant, perennial water is available from two springs located on the east side of the property, which is used to supply current ranch needs.
  • High solar exposure, with an average solar insolation level of 6.95 kWh/m2/day (compared to that of Death Valley, CA at 6.4 kWh/m2/day, and Fairbanks, AK at 3.1 kWh/m2/day).
  • Monthly average wind speeds between 2 – 7 mph, with prevailing winds from the northwest during the spring and summer months and storm winds from the south during winter months.
  • Gravel-, sand- and clay-loam soils with moderate to high fragility, generally low to moderate permeability, high runoff potential, and high erosion hazard.
Base map of existing conditions

The following issues were identified in the assessment which will pose significant ongoing challenges to the landowners in meeting their goals unless rectified:

  • Difficult/cumbersome access across highway and in steeper portions of property on both east and west sides.
  • Public vehicle access through the heart of the property and Ranch HQ via the county road has led to trespassing on the property and increased security risks.
  • Overgrazed and degraded pastures that generate a large amount of surface run-off contributing to soil erosion down watershed. Pastures have very low organic matter content, low moisture retention, low litter and perennial cover, and very low biological activity, and their current productive capacity is a small fraction of what they can be.
    • Lack of vegetative cover is significantly contributing to the runoff issues noted above, which guarantees decreasing soil fertility with each passing year.  Living root mass is the most effective means of infiltrating water into the soil where it can be productively used by plant roots and soil biota.
    • Soil compaction due to loss of soil structure, and thus decreasing water infiltration and water storage capacity. The pore spaces that are created in a healthy, living soil from plant roots, the exudates they produce, and the soil biology they help to protect and sustain are diminished or gone entirely in some places.
  • Unmitigated point-sources of high-volume, high-energy run-on from the various highway drainage systems onto the western half of the ranch, which have contributed significantly to headcutting, incising of drainages, overall dehydration of lower pasture zones and loss of topsoil.
  • Minimal income generation from the ranch.
Influencing sector map

Key initial considerations recommended for further investigation in a whole-site design process included:

  • Installation of passive water harvesting systems above and throughout lower pasture zones west of the highway to slow, spread, and ultimately infiltrate into the soils of the pastures an estimated 20-45 million gallons of rainwater that is currently running off of and eroding the compacted soils during every average rain year.
  • Broadacre silvopasture system (the integration of tree crops and animal grazing systems) designed around mainframe passive water harvesting features. 
  • Installation of appropriate energy dissipation structures at all culvert outlets to de-energize discharge flows, reducing and ideally halting their ability to contribute to further downstream incising of drainage paths. 
  • Drainage rehabilitation to halt further head cutting/incision and initiate healing processes in incised drainages.
  • Assume responsibility for county road maintenance and add gate to close off to non-resident vehicle traffic . Limiting vehicle traffic to that of property residents, county personnel, and utility maintenance staff should significantly reduce the amount of trespassing on the west side of the property that occurs from the county road. 
  • Add residences to the property for family/community members. Increasing the number of people who are living on the property has the potential to help with almost all of the development and maintenance logistics, discourage the frequency of trespassers, and generally create more of a community feel on the property. 
  • Develop “glamping” sites throughout property for community members and visitors. Increasing the number of desired people who are on the property at any given time and their reach across the property has the potential to discourage the frequency of trespassers and generate income streams for the landowners.  
  • Plant privacy screens/windbreaks along boundary and internal fences (especially along the county road and highway) to enhance visual and acoustic privacy.
  • Intensively-managed ruminant livestock, pasture rejuvenation using the recommended passive water harvesting system, and silvopasture plantings in pasture areas.
  • Multi-yield fuelwood and livestock fodder production using coppicing and pollarding to maintain silvopasture blocks. 
  • Wood-fired cooking and space and water heating systems in current and future residences and shops heated with small-diameter coppice stick fuels produced from silvopasture systems. 
  • Explore potential reconfiguration of essential circuits in the residences to be primarily powered by a solar PV-charged battery bank, with the utility connection as a backup charging source.
  • Creation of land-centric enterprises serving local, regional and tourist demographics.