Watershed Materials - Technology for New Concrete Blocks
The block with a smaller carbon footprint.

Mark West Watershed Block - ASTM C90 Compliant

The linen tint of the Mark West Watershed Block originates from minerals from two quarries in Sonoma's Mayacamas Mountains. ASTM C90 compliant.

Mark West Watershed Block™

ASTM C90 Compliant - Produced in Napa, California

The linen tint of the Mark West Watershed Block originates from the combination of crushed basalt from the BoDean quarry west of Calistoga with crusher fines from Nun’s Canyon quarry, both in Sonoma County’s Mayacamas Mountains, named for a Native American tribe that lived in the Maiya'kma village on the west slope near present day Calistoga. The BoDean Mark West Springs quarry is the first in the world operate 100% under photo-voltaic (PV) solar power.

The Mark West Watershed Block weaves aesthetics and sustainability with performance. Reduced cement lowers the block’s CO2 footprint compared to traditional concrete block. The block’s natural beauty arises from regional minerals in place of expensive artificial colorants. The Mark West Watershed Block meets or exceeds ASTM C90 specifications, encouraging engineers and architects to specify the block with confidence.

Nominal Dimensions: 4x8x16”, 6x8x16”, 8x8x16”, Bondbeam blocks 6” & 8” high. See detailed actual measurements here.

Dry Density: 125-130 pcf (standard-weight)

Weight: 21.7 lbs per 4” block, 29.6 lbs per 6” block, 43.4 lbs per 8” block

Compressive Strength: Greater than 1,900 psi (ASTM C90 compliant)

Water Absorption: Less than 13 pcf (ASTM C90 compliant)

Linear Shrinkage: Less than 0.065% (ASTM C90 compliant)

Thermal Conductivity: 0.81-0.93 W/m°C

Acoustic Reduction: 40-50 dB (40 cm wall 500Hz)



The Mark West Watershed Block offers an improved sustainability profile compared to traditional concrete block.

  • Incorporates locally sourced, unwashed aggregate, reducing water use and diesel emissions from transportation
  • Contains recycled post-industrial quarry byproducts
  • Reduces cement, an expensive and hugely polluting binder responsible for 6% of humanity's CO2 footprint
  • Avoids energy intensive steam curing
  • Increased density provides natural thermal mass that can offset heating and cooling needs

Product Availability

The Mark West Watershed Block is produced in Watershed Materials' factory in Northern California using locally sourced materials. In keeping with our commitment to environmental sustainability - and to reduce transportation costs - the Stanford Watershed Block is available within a 250 mile radius of the San Francisco Bay Area. For certain projects outside this radius, Watershed Materials can provide carbon offset credits for extended transportation.

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