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

Lime White Watershed Block - ASTM C90 Compliant

The Lime White Watershed Block uses zero cement and offers a bright glacier white appearance that emerges from lime and white clay. ASTM C90 compliant.

Lime White Watershed Block™

ASTM C90 Compliant - Produced in Napa, California

The Lime White Watershed Block offers a remarkable step forward for modern masonry - a zero cement formula, a stunning glacier white appearance and a novel mix design with a dramatically increased sustainability profile. The block uses no Portland cement - a notorious polluter responsible for 6% of humanity’s CO2 emissions - instead deriving strength from the high compression lithification of lime, recycled ground granulated blast furnace slag and natural clays.

The Lime White Watershed Block offers unique aesthetics and sustainability along with standard industry performance. Eliminated cement lowers the block’s CO2 footprint compared to traditional concrete block. The bright glacier white appearance emerges from the unique lime, slag and clay aluminosilicate binder. The Lime White Watershed Block meets or exceeds ASTM C90 specifications, allowing 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: 120-125 pcf (medium-weight)

Weight: 21.1 lbs per 4” block, 27.4 lbs per 6” block, 42.2 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 Lime White Watershed Block offers an improved sustainability profile compared to traditional concrete block.

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

Product Availability

The Lime White 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.

Product Downloads