Four-inch Topsoil Rule

Topsoil a Dirty Subject

In 2015 the Iowa Department of Natural Resources revised its topsoil rule so that a developer or home-builder would be allowed to decide how much topsoil to replace, if any, following construction.  Previously the rule required four inches of topsoil to be returned.  Now it is up to cities to establish their own topsoil requirement.

Local Communities can implement their own rules 

Local communities have begun to take action requiring that topsoil be returned to building sites.   Some communities are looking at a requirement that existing topsoil must be preserved and replaced uniformly after construction.  Other communities are looking at requiring several inches (such as 4) be returned following construction.

Coralville requires that existing topsoil must be preserved and reapplied after construction in a uniform uncompacted manner (Coralville ordinance, chapter 159).

North Liberty requires the topsoil that was present on a building site to be returned in an uncompacted manner (ordinances 155.01(2), 155.02, 156.03) on any development that is at least an acre or on any lot that is part of a development that is at least an acre.

The City of Cedar Rapids has an ordinance that requires 4-inches of topsoil to be restored to a lot after construction, allowing 3-inches of topsoil to be restored and counting the sod as an additional inch.  Originally the city of Cedar Rapids proposed an ordinance that would have required eight inches of topsoil to be restored; due to resistance from homebuilders, that ordinance was never brought to the city council.  The City of Cedar Rapids then hired a company from Des Moines (Team Services) to test the soil on 26 lots to determine how effectively topsoil was restored after construction.  To see the results.  The company tested soil from 26 lots, in 13 developments, involving 9 developers, with the houses built in the last 6 years.  The results clearly showed that the lots did not have topsoil restored instead the soil on the lots was compacted clay.  Todd Dorman, columnist for the Cedar Rapids Gazette, wrote about the results in his column on June 23, 2016. 

For more information on local ordinances

You can decline to purchase a home without topsoil

You can also make choices about the home you purchase.  If the lot has no topsoil, you can walk away.  In doing so, you will protect yourself, protect your property, and protect water quality.  See more.


Topsoil became a dirty subject for conservationists arguing to retain 4 inches of topsoil after new development construction and developers who say it's simply too expensive. 

The Iowa Chapter opposed the rule change. 

After learning that the DNR had no plans to prepare a cost-benefit analysis, the Iowa Chapter sent a letter to Chuck Gipp, the DNR Director, and other DNR staff involved in developing the topsoil rule.  Read the letter.

The Old Rule Was Better Than the Rule that Was Adopted.

The new rule modified a general permit requiring topsoil preservation for construction sites that disturb one acre or more that was adopted in the fall of 2012. That rule called for retaining four inches of topsoil spread on the surface, unless infeasible.  Reasons for the topsoil restoration are to help increase water infiltration into the soil, to prevent runoff and erosion, to retain healthy soil and to lessen the degradation of water quality.  Topsoil retention will aid the home-buyers in their efforts to establish landscaping on their lots – grass, trees and gardens. 

New Rule Does Not Protect Homeowners


In 2013, developers and home-builders started complaining about the high costs of implementing the rule.  Governor Branstad initiated a stakeholder group, packed with developers and home-builders, for the purpose of reviewing the rule and proposing changes.  The governor claimed that forming the stakeholder group is about injecting common-sense into the regulatory process.  Unfortunately common-sense did not prevail.

During the public comment period for the proposed rule, homeowners flocked to the DNR complaining about properties where no topsoil was returned to the building site.  Homeowners thought they were purchasing a lot with topsoil, only to find that the sod was laid on compacted soil with no topsoil returned.  They related horror stories about the inability to grow trees, grass, and gardens.  They told painful stories about the costs that they either had incurred or were quoted to remedy the situation.  If is infinitely more expensive for a homeowner to restore the topsoil than for a developer to do it in the first place.  Furthermore the price of returning topsoil to a lot would be bundled into a homeowners loan at the time he or she purchased the property.  Getting that loan is easier than trying to get a separate loan to complete the work that the contractor did not perform.

Topsoil holds water on the land and also holds fertilizer.  When the topsoil has been stripped from a lot and not returned, water runs off the land, exacerbating flood risks.  To make matters worse, fertilizers do not stay in the ground, instead running into Iowa's lakes, rivers, and streams.