Who is the specific person responsible for this project?
The city’s consulting engineer, Andrew Budde, from Bolton & Menk is responsible for plan preparation and execution. Additional staff involved include inspector from Bolton & Menk; Andrew Eslinger, Shorewood Street Inspector; Larry Brown, Director of Public Works, and Greg Lerud, City Administrator.
What are the sources of funding for this project?
The city will issue bonds that are payable from stormwater utility charges and franchise fees. The city has estimated cost estimates for all capital improvement projects. Included in those estimates is a contingency (typically 5% of the total project costs) that is available if there are unforeseen costs or changes. The city puts a great deal of effort into plan development on the front end so we can minimize changes as the project begins.
What are the specific steps the project will take to avoid harm to residents, workers, properties, property values, natural habitat, and aesthetic enjoyment?
Good planning, use of best practices, an invitation for public involvement in the planning process, and ongoing communication between the city and the residents throughout the project. Also, following the requirements of oversight/participation by outside entities, such as the Minnehaha Creek Watershed, and Hennepin County Regional Rail Authority, where appropriate.
How will the project affect the high ground water table?
The soil borings taken on the Smithtown Pond site identified groundwater at four-feet to nine-feet below the ground surface immediately after the boring rod was removed. The borings were taken in August of 2020 and represent one data point. Typically, groundwater elevations will fluctuate based on the season, precipitation and characteristics of the soils. The normal water levels of the ponds are generally within one-foot of the existing groundwater elevations and will have little to no impact on the surrounding groundwater elevations.
Will the project introduce contaminants into the soil and local wells?
The stormwater ponds will capture sediment and pollutants from the surrounding stormwater runoff. Many pollutants are attracted to and adhere to the sediment particles, which sink and collect at the bottom of the pond over time. Contaminants that float, such as oils and trash, stay at the surface and are deposited at the edges of the pond. Sediments are typically cleaned from the ponds 20 to 40 years after its construction. All the soils in the pond area are classified as hydrologic soil C/D, which are not conducive to infiltration. These types of soils are typically used to line ponds in areas of sandier soils and will therefore restrict any potential migration of stormwater from the pond. The surrounding residential wells have static water levels approximately 90 feet deep. Due to the poor infiltration properties of the onsite soils and the depth to the existing wells, the wells will not be contaminated by the stormwater pond.
What is the plan for replanting?
A number of trees on the city property will be removed as a part of this project – there is simply no way to avoid it. The city will keep every good-quality tree possible. Ash trees and other trees that have been deemed to be in poor condition by the city arborist will be removed if they are near the limits of the project area. This will prevent the city from having to come back in the future and, at a higher cost, remove trees that are known to not be healthy or subject to the Emerald Ash Borer.
The city plans on implementing a significant replanting effort at the conclusion of the excavation work. The city has prepared renderings of what this area will look like, but they are for illustrative purposes only. The city council is on record as stating that they want as minimal tree removal as possible, and robust replanting of trees and other plantings at the conclusion of the project. That specific plan will be reviewed and approved as this construction phase of this project nears completion.
What will be the measure of success for this project?
The city is attempting to address a number of stormwater issues in this part of the city. Specific project areas to be impacted by these ponds include; Strawberry Lane, Strawberry Court, Peach Circle, Shorewood Oaks, Freeman Park, and Grant Lorenz. In addition to trying to address rain events, runoff, and erosion, the ponds will provide treatment of stormwater. Specifically, there will be a reduction in phosphorus going into Lake Minnetonka, and more generally, success will be determined through observation of streets and private property following rain events. Are instances of standing water reduced? Is seasonal, or by event, flooding reduced? Those types of “non-scientific” observations, as well as calculations of phosphorus and other contaminants being prevented from going to Lake Minnetonka, will be the measure of success.
What safety steps will be taken for such considerations as school children, bus, and car access, drowning risk, etc.?
There will not be vehicle access to this property, except for authorized city vehicles. There will be an accessible walking trail that connects the Minnetonka LRT to the sidewalk on Smithtown pond. This area will be park-like when the work is completed. The city will be working with the Minnehaha Creek Watershed for educational displays to show how stormwater ponds function and their value to the environment. There are no plans to fence in the ponds. The ponds are designed with a minimal slope and a “bench” on the slope that would help prevent someone from rolling into the water.
What is the plan for mosquito control?
By moving surface water from these areas into the pond, we believe that it will reduce the amount of stagnant water that presently sits in many places – back yards, ditches, etc., which are primary breeding grounds and where there is no current treatment for mosquitos. The Metro Mosquito Control District has a responsibility metro-wide for the control of mosquitos, and these ponds would be treated by that organization.