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Soil Amendment Program

Before a newly constructed premise may be landscaped, property owners must amend their soil with compost so the soil more efficiently retains water. This rule applies to all new residential, commercial, government and industrial properties within Denver Water’s service area.

Importance of Soil Amendment

Soil amendment is required prior to landscaping the premise. Amending your soil with compost has multiple benefits. Organic matter (compost) particles can hold moisture in the soil for extended periods, allowing water to be available to plants over a longer period of time. Compost can provide small amounts of the key nutrients nitrogen, phosphorus and potassium (N-P-K) and also increases microbial activity, which improves plant root growth. Compost also opens clay soils, allowing better drainage, and closes sandy soils, preventing water from leaching away too quickly.

Denver Water operating rules that apply to soil amendment and limits on use:

Operating Rule 14.02.4 — Soil Amendment for Irrigation of Turf at Newly Licensed Premises. Proof of proper soil preparation is required before installation of plant material. Penalties may apply if soil amendment is not completed prior to the installation of plant material. Proper soil amendment is the equivalent of adding approved compost at a rate of four cubic yards per 1,000 square feet of permeable area, incorporated (roto tilled) to a depth of six inches.

Operating Rule 3.03 b — Limits on Use. Unmetered use of water for construction is permitted only until the water service is activated, as required in Rule 2.02.1, or the Water Supply License is cancelled under Rule 2.12, whichever occurs first. Landscape irrigation and occupancy of the premises prior to the installation of a meter are prohibited and shall constitute unauthorized use of water.

Properties meeting any of the following conditions are not required to amend the soil prior to landscaping:

  • Water tap for indoor use only.
  • Property with less than 300 square feet of amendable area. 
  • Outdoor use limited to planter boxes. 
  • Outdoor use with nonpermeable areas only.

The watering of landscape and/or occupancy of the premises prior to the installation of a meter are prohibited and shall constitute unauthorized use of water.

To Pass Soil Amendment Approval

Prior to the installation of any plant material, including sod, apply a minimum of 4 cubic yards of soil amendment product per 1,000 square feet of permeable area.

This soil amendment product must be incorporated or rototilled to a depth of 4-6 inches. The site must be raked smooth and finish grades must be established. Rocks and debris over 1-inch diameter that may interfere with planting and maintenance operations must be removed.

  • Native grass-seeded areas may incorporate amendment at a rate of 2 cubic yards per 1,000 square feet. Seed mixes are required for submittal along with a map outlining the area.
  • Tilled soil amendment product is required for all permeable area of the property, including tree lawn and right-of-way adjacent to the property for which the property owner is responsible for planting and maintaining.
  • Soil amendment is not required within 5 feet from the foundation of the property.
  • Scraped properties will require compost only if a new tap and license is required and the existing landscape has been removed from the property as determined by the inspector.
  • An application rate of 12 cubic yards per 1,000 square feet is required for amended topsoil.

To Obtain Soil Amendment Approval

Provide documentation (invoice or load ticket) of soil amendment product, and a plot survey map with square footage of the amended area for inspection purposes. The load ticket must include the type of soil amendment product, and the address(es) it will be applied to.

Approval will be arranged once documentation has been received and product approved:

You will be notified of soil amendment approval status by phone or email. All properties are subject to spot inspections.

If the property is served by a master meter distributor, the distributor’s representative will be notified of the soil amendment approval via email within the next business day.

Winter Extension

When weather and ground conditions prevent completion of the soil amendment requirement, Denver Water may extend the completion date to no later than June 1. The customer may request a winter extension by calling Denver Water’s Customer Care department at 303-893-2444 or emailing [email protected] to request the extension. The soil amendment must be approved prior to landscaping the premise in the spring.

Operating Rule 14.02.4 — Soil Amendment for Irrigation of Turf at Newly Licensed Premises. Proof of proper soil preparation is required before installation of plant material. Penalties may apply if soil amendment is not completed prior to the installation of plant material. Proper soil amendment is the equivalent of adding approved compost at a rate of 4 cubic yards per 1,000 square feet of permeable area, incorporated (roto tilled) to a depth of 6 inches.

Phased Projects

Large projects that have landscape installed in segments over the life of the project may qualify for phased approvals. A complete site plan identifying the different phased areas must be submitted for review and approval prior to initial meter set.

Class I and Class II Compost 

Compost Classifications

Compost products that meet a minimum of Class II specification are recommended to achieve the best results.

Minimum Stability Indicator CLASS I
Stable — Very Stable
CLASS II
Stable
pH 6.0 – 8.0 6.0 – 8.2
Ag Index (Nutrients/Na+CI) Must report Must report
Soluble Salts Maximum 5 mmhos/cm Maximum 10 mmhos/cm
Carbon/Nitrogen Ratio < 12 < 18
Ammonia-N/Nitrate-N < 4 < 6
Bulk Density (lbs/CY) Must report Must report
Primary, Secondary,Trace Elements Must report Must report
Organic Matter; Moisture Content (% / CY) Must report Must report

Local Class I and II Compost Suppliers

If you are a compost supplier and would like to have your product added to the list, submit a complete soil analysis to [email protected].

Supplier/Address Phone Manufacturer/Product Name
A-1 Organics/16350 WCR 76, Eaton, CO 80615 970-454-3492
800-776-1644
A-1 Organics/BioComp, EcoGro
Aesthetic Alternative Recycling /2840 S. Holly Pl. Denver 80222 303-756-8660 Compost
Ainsworth Rock Sales /5600 No. Washington St. Denver 303-295-2990 B.O.S.S./Class I Black Tea, 5 Way, 5 Organics
All Demolition Excavating Company /11650 W. 68th Ave. Arvada 303-467-3366 Colorado Landscape Materials/Compost #5W1235
Alpine Waste & Recycling / 7475 E. 84th Ave., Commerce City, 80022 303-744-9881 Compost
APC Landscape Supply /14802 W. 44th Ave. Golden 303-279-6611 A-1 Organics/BioComp
Bedrock Landscaping/5401 W. 52nd Ave. Denver 80212 303-637-9743 A1 Organics/BioComp, B.O.S.S/Class I Black Tea, 5 Way, 5 Organics
Bighorn Landscape Materials/ 7721 S. Parker Rd. Aurora 80016 720-306-9018 A1 Organics/BioComp, Premium 3
B.O.S.S. Compost, Inc. /16700 County Rd. 12 Ft. Lupton 303-659-5958 Class I Black Tea, 5 Way, 5 Organics
CMT Excavating /P.O. Box 935, Indian Hills, CO 303-489-3036 Compost Sample B
Colorado Landscape Materials /6300 W. 49th Dr, Wheat Ridge 303-456-9944 Compost #5W1235
Colorado Landscape Supply /8181 Quebec St., Commerce City 303-995-1351 Compost
Colorado Materials Inc. /1821 Boston Ave Longmont, CO 80501 303-682-2314 CMI Compost, Western Disposal Services/Compost
Colorado Soils LLC / 8604 County Road 18  Johnstown, CO 80534 970-217-1535 Compost, Amended Topsoil
Denver Arapahoe Disposal Site (DADS) Landfill, Waste Management of Colorado / 3500 S. Gun Club Road, Aurora CO 80018 303-876-2620 Compost
Designs by Sundown /4501 S. Santa Fe Dr. Littleton 303-356-8488 Humalfa/Natures Prescription
Direct Landscape Supply /2901 S. Santa Fe Dr. Englewood 303-781-2290 B.O.S.S/Class I Black Tea, 5 Way, 5 Organics, CMT Excavating/Compost Sample B
Four D Farms /9743 County Rd 16 Fort Lupton, CO 80621 970-534-0811 Compost
Front Range Material, Inc. /1019 8th St. Ste. 300 Golden 303-425-9992 CMT Excavating, Inc./Compost Sample B
Green Valley Turf Farm /13159 N. US Highway 85 Littleton 303-798-6764 A-1 Premium 3 Compost
GreenStock Materials /10886 Hwy 93 Golden 303-494-7625 A-1 Organics/BioComp
Humalfa, The Organic Fertilizer, LLC /26874 CR 65, Iliff, CO 80736 970-466-7981 Natures Prescription
James Nursery /7900 York St. Denver 303-288-2424 Humalfa/Natures Prescription
Jared’s Nursery & Garden Center /10500 W. Bowles Ave. Littleton 303-979-6022 B.O.S.S/Class I Black Tea, 5 Way, 5 Organics
Jensen Sales Co. /8980 S. Santa Fe Dr. Littleton 303-791-4250 Supreme Compost
Jones Fine Sand 303-289-1428 B.O.S.S/Class I Black Tea, 5 Way, 5 Organics
Nick’s Garden Center /2001 S. Chambers Rd. Aurora 303-696-6657 B.O.S.S./Class I Black Tea, 5 Way, 5 Organics
Pine Lane Nursery /18200 Apache Dr. Parker 303-841-3009 Humalfa/Natures Prescription
Pioneer Sand Co. /463 Airport Blvd. Aurora 303-340-1440 A-1 Organics/BioComp, Planters Mix**
Pioneer Sand Co. /11250 Dillon Rd. Broomfield 303-456-4212 A-1 Organics/BioComp, Planters Mix**
Pioneer Sand Co. /7608 Highway 93 Golden 303-279-4758 A-1 Organics/BioComp, Planters Mix**
Pioneer Sand Co. /11010 Irma Dr. Northglenn 303-252-1095 A-1 Organics/BioComp, Planters Mix**
Pioneer Sand Co. /8189 W. Brandon Dr. Littleton 303-791-3535 A-1 Organics/BioComp, Planters Mix**
Pioneer Sand Co. /11731 N. Hwy 83 Parker 303-841-3737 A-1 Organics/BioComp, Planters Mix**
Pioneer Sand Co. /6379 Valmont Rd. Boulder 303-440-7625 A-1 Organics/BioComp, Planters Mix**
Pioneer Sand Co. /13505 E. 112th Ave. Brighton 303-288-6007 A-1 Organics/BioComp, Planters Mix**
Prime Materials, LLC /8251 I-76 Frontage Rd. Henderson 303-655-0431 B.O.S.S./Class I Black Tea, 5 Way, 5 Organics
Renewable Fiber /2600 W. Oxford Ave. Englewood 303-798-1292 Premium Dairy D/ BioCompost, Royal Compost*
Rock N Materials, LLC 303-981-3573 B.O.S.S./Class I Black Tea, 5 Way, 5 Organics
Santa Fe Sand and Gravel /6601 S. Santa Fe Dr. Littleton 303-794-5960 Cottonwood Dairy, 5W1235
Select Materials (wholesale only) 303-857-4688 5W Compost
Silver Crown Landscape Materials /12185 N. Dumont Way Littleton 303-683-0200 Compost #3, Compost #5W1235
Simplot Partners /4195 Oneida St, Unit H Denver 720-941-0646 A-1 Organics/BioComp
Storjohann Trucking LLC /10701 E. 120th Ave., Henderson 80640 303-324-2263 A-1 Organics/Bio Comp, Premium 3, Planters Mix**
Titan Landscape Materials /9881 Titan Park Cir, Littleton 80125 303-960-3408 B.O.S.S/Class I Black Tea, 5 Way, 5 Organics
Western Disposal Services /5880 Butte Mill Rd. Boulder 80301 303-618-8600 Compost

*pH at upper limit of a Class II compost.

**Limited to use in excavated planting beds on a case-by-case basis.

List updated May 4, 2017