Adopt Ordinance #19-03 Amending the Definition of Topsoil (Project No. 18-146)

The City Council introduced Ordinance #19-03 on February 26, 2019 and per the City Charter, it is now eligible for adoption.

In the mid-to-late 2000s, the City adopted a new development requirement, requiring all new construction to establish 4" of premium topsoil. The intent was to reduce the consumption of water related to lawn irrigation. Through several appropriations request to the Minnesota Department of Natural Resources for additional public wells, the City needed to implement additional water conservation measures due to the high consumption of water in summer months compared to peer communities. A large portion of this consumption was due to lawn irrigation in very sandy soils. While the current standard is quite effective in water conservation, Staff believes it is an appropriate time to evaluate the cost-benefit ratio. The standard has not reduced the amount of development in the community, but the City has received much feedback on the standard.

For several years now, the City has been receiving feedback on the current topsoil requirement both in the field, as well as in other forums such as the Contractor's Networking Event hosted by the City. More recently, the City received a written request from Capstone Homes to consider revising the topsoil standard by eliminating the specification for Premium Topsoil Borrow (a now former MnDOT specification). The request identified two negative effects of the current topsoil requirement. First, that the topsoil is doing too good of a job in terms of holding water. Capstone acknowledges that many homeowners are likely not adjusting their irrigation systems to account for the topsoil and are actually contributing to the problem. Secondly, Capstone identified price as a concern compared to the cost of a less stringent definition of black dirt.

Staff has had multiple discussions with the Environmental Policy Board (EPB) regarding this topic. The EPB requested Staff to gather information on what similar peer communities with similar sandy soils require, and review the purpose of the requirement in these communities to see if the analysis is a fair comparison. Staff looked at the requirements for communities such as Andover, Big Lake, and Blaine, all of which have a topsoil requirement and are growing communities on sandy soils. Elk River was also contacted but due to significant opposition, they did not adopt a topsoil requirement. Rather, Elk River implemented a rebate program focused on improving irrigation systems.

A Notice of Public Hearing was published in the Anoka County UnionHerald.

Review of Peer Communities Topsoil Requirements

Staff contacted multiple communities that are all situated within the Anoka Sand Plain. These comparisons generally have a sandy base or native soils with less water holding capabilities. A summary of each community's standards are attached to this case. Based on this review, it is clear that Ramsey has a much more stringent approach to topsoil. It seems that communities that have adopted a topsoil requirement have done so with an intention of reducing demand on groundwater while also assisting with vegetation establishment.

Cost Comparison

Staff has also obtained cost estimates from Capstone Homes as part of this request. The information helps illustrate the cost per lot, which is ultimately passed on to the Buyer. The topsoil requirement is applicable to any lot in any district being developed with a new principal building, including those on private wells which still draw from groundwater supply. These costs are representative of the typical residential lot sizes being developed currently.
 

Approximate Lot Size	Estimated Cost of Premium Topsoil Borrow	Estimated Cost of Regular Black Dirt	Price Difference
6,000 sq. ft. (0.15 acres)	$3,690	$2,250	$1,440
10,800 sq. ft. (0.25 acres)	$5,740	$3,500	$2,240
43,560 sq. ft. (1 acre)	$10,660	$6,500	$4,160
108,900 sq. ft. (2.5 acres)	$19,000	Unknown	Unknown

Alternatives to Premium Topsoil Specification

The present request is not to entirely eliminate the topsoil requirement, but rather to modify it to something more consistent with surrounding communities. This would still provide improved soil characteristics, but at a more cost effective ratio. This could also help address recent concerns raised by homeowners about standing water and spongy areas in backyards when irrigation systems are not adjusted properly.

Advances in irrigation technology over the past decade have made it easier and more cost effective to conserve water through better sprinkling habits. Smart controllers can be connected via the internet to current and local weather information and historical data to assist with reducing unnecessary waterings. Also, multiple soil moisture sensors can be utilized in different parts of a yard to ensure that the irrigation system doesn't turn on that zone unless there is insufficient moisture in the soil. These sensors are typically $150 or less. The message coming out of the University of Minnesota's Extension team is that water efficient irrigation systems, not new turf varieties or soil amendments such as topsoil, have become the most cost effective means to reducing non-consumptive water usage.

City Code now requires any new irrigation system to have a water efficient technology. However, there are many existing systems that could be retrofitted. This comes at a higher cost than upgrading a new system. While not being proposed at this time, the City could consider developing a rebate program that would provide a financial incentive to owners to upgrade existing systems. Additionally, the City could provide incentives for a simple irrigation system tune-up that would maximize efficiency and provide an educational opportunity for the Homeowner. It may also be possible to find grant funds to establish and offer these rebate programs.

Weather/Precipitation/Landscape

The largest factor in water usage has always been and will likely always be the weather and precipitation. With newer systems, weather can be  factored into the programed run-times. The water usage data from the City does show a clear correlation between reduced precipitation and increased water usage.

Additionally, tree canopy cover can also play a significant role in watering needs of a yard. Shady portions of a lawn require much less water than sunny portions. This demonstrates the effectiveness of installing several moisture sensors, with the ability to isolate zones.

Recommendation

The EPB and Planning Commission recommend approval of this Ordinance that keeps, but modifies the topsoil standard for reasons stated above.

The Public Works Committee received an update from Staff on the proposed Ordinance Amendment on February 19, 2019. By consensus, the committee supported presenting the Ordinance Amendment to the City Council.  In addition, the Committee requested that Staff consider tailoring proposed water conservation educational materials differently to property owners of larger rural lots on private wells.


Alternatives

Alternative 1: Adopt Ordinance #19-03 as presented. The EPB and Planning Commission support this alternative.

Alternative 2: Do not introduce the Ordinance Amendment to amend the current definition of topsoil. 

This case is being handled as part of Staff's regular duties.

Both the EPB and the Planning Commission recommend adopting Ordinance #19-03.

Motion to waive the Charter requirement to read the ordinance aloud and adopt Ordinance #19-03 amending the definition of topsoil.

Roll Call Vote

Councilmember Kuzma
Councilmember Riley
Councilmember Musgrove
Councilmember Heinrich
Councilmember Shryock
Mayor LeTourneau