Taking a Strategic Approach to Water Quality Management

By Tony Havranek, Sr. Ecologist, WSB

Boating, fishing, swimming, and enjoying a day near a lake, river, or stream is part of Minnesota’s culture. Unfortunately, nearly 40 percent of Minnesota’s lakes and streams are included on the Minnesota Pollution Control Agency’s (MPCA) Impaired Waters List. (See the list at https://bit.ly/2BwTk3r.)

Meeting surface water quality standards requires monitoring pollutants that can affect the physical, chemical, or biological makeup of surface water. Phosphorus is one of the main pollutants in the state’s bodies of water. Phosphorus is a pollutant that comes from both external and internal loading sources. Today, Minnesota law limits the use of fertilizers containing phosphorus, but prior to these limits, phosphorus was widely used in several commonly used chemicals settling in our lakes, rivers and streams. Meeting water quality standards requires a reduction of phosphorus in the water column. A water column is the vertical section of water from the surface to the bottom of a body of water.

External sources include stormwater runoff, atmospheric deposition, and directed pipe runoff. Internal sources include sediment suspension, aquatic vegetation, and an overabundance of rough fish. Both internal and external loading sources contribute to surface water quality degradation.

Managing water quality is not only important to the community and the people who live and work there, but it also drives ecological integrity. Because of this, water quality is regulated by federal, state, and local governments.

Where to start
With the appropriate funding and expertise, it is possible to solve water quality challenges and get bodies of water removed from the MPCA Impaired Waters List. Fortunately, numerous funding resources are available through grants, partnerships, and coalitions.

Since water is continuous across landscapes, developing partnerships is often the most cost-effective way to approach managing water quality. It lessens financial burdens and helps many communities achieve long-term success. It also creates opportunities for communities to create long-term plans to improve and protect water quality.

To begin to make improvements, it’s important to understand a community’s water quality issues. Start putting the pieces of the puzzle together by quantifying the scale and source of the pollutant before selecting an approach. The MPCA’s website offers information on a body of water’s total maximum daily load (TMDL) at https://bit.ly/2BbsrVH.

The TMDL is the maximum amount of pollutant a body of water can receive without exceeding water quality standards, and allocates pollutant loads from internal and external sources. In other words, the TMDL identifies all sources of a pollutant and determines how much each source must reduce its contribution.

TMDL implementation actions
Once the TMDL is identified for each body of water, a plan of action can begin to be shaped. Several methods can be implemented to begin to improve water quality.

Public education and outreach. Fertilizers have a major impact on water quality and ecosystems, creating a chain reaction. Excess phosphorus found in fertilizers creates algae blooms. As algae decomposes, oxygen is removed from the water. A lack of oxygen in an aquatic ecosystem effects the native species in a body of water. Educating the public of the harmful effects caused by fertilizer runoff can help limit the amount of phosphorus or other nutrients that flow into bodies of water.

Structural best management practices (BMPs). The MPCA defines a BMP as a stationary and permanent structure that is designed, constructed, and operated to prevent or reduce the discharge of pollutants in stormwater. BMPs can be used for on-site or regional treatment and help a community take a more strategic approach to managing its water quality.

Carp management. Internal loading of phosphorus can be caused by an overabundance of the invasive common carp. High levels of phosphorus cause algae blooms, reduced clarity, loss of aquatic plant and fish habitats, and a threat to human health. Managing and mitigating carp populations improves long-term overall water quality and ecological integrity.

Vegetation management. Invasive aquatic vegetation displaces native vegetation and can release phosphorus into the water column. Vegetation management can help solve this problem. Strategically placed native vegetation can help protect soil from erosion and reduce surface water runoff. Stormwater is then held in place and slowly released, rather than flowing directly into the body of water. Native aquatic vegetation can also help reduce phosphorus-laden sediments through wind and wave action.

There isn’t a silver bullet that can solve a community’s water quality challenges at once, but these are several proven options that can lead to improved water quality and ecological integrity.

This article was originally published in the January/February 2019 issue of League of Minnesota Cities magazine.

Slope Failure

When people think of slope failure or geohazards, they think of landslides and mudslides in mountainous regions like California. Those of us living in the Midwest don’t typically worry about property damage or disruptions in public services due to slope failure. Unfortunately, slope failure impacts a wide range of landscapes, even those considered relatively level. In fact, in the Twin Cities there have been increasing numbers of slope failures that significantly impacted infrastructure and property. The most recognizable example is probably the 2014 slope failure along the West River Parkway in Minneapolis. This slope failed after more than 11 inches of rain fell in two days, impacting a popular recreational trail as well as a major health care facility. Repairs were completed in 2016, and cost $5.639 million [i].

Slope failure is a geohazard that impacts many types of infrastructure, from individual homes to municipal storm sewer networks to oil and gas pipelines. In fact, the Pipeline and Hazardous Materials Safety Administration requires that natural gas and hazardous liquids pipelines develop risk assessment programs for slope failures in their systems. Likewise, many municipalities are beginning to incorporate these types of risk assessment programs into their own planning activities.

So what causes slope failures? Like all geohazards, the causes are myriad and complex. Establishing a framework of how the physical processes behind slope instability function is crucial in determining risk.
Simply put, slope stability is based on the interaction of two forces: driving forces and resisting forces. Slope failures occur when driving forces overcome resisting forces. The driving force is typically gravity, and the resisting force is the slope material’s shear strength.

When assessing a slope’s stability look for indications that physical processes are decreasing shear strength. These can include:

Weathered geology: Weak, weathered bedrock, jointed rock, or bedrock that dips parallel to the slope can decrease stability.
Vegetation removal: Droughts, wildfires and humans can remove vegetation from the slope, decreasing stability.
Freeze/thaw cycles: Water in rock joints or in soils can decrease slope stability.
Stream action: Rivers can erode the bottom of the slope, called the toe, decreasing stability. This can occur over time through normal stream action or catastrophically during flood events.
Human modifications: Humans modify stability through actions such as excavation of the slope or its toe, loading of the slope or crest, surface or groundwater manipulation, irrigation, and mining.
Slope angle: Steeper slopes tend to have greater risks for instability.
Soil type: Soils have variable amounts of shear strength, dependent on factors such as soil texture, pore water, and particle cohesion.
Water sources: Water works in many ways to reduce shear strength. For example, pore water pressure in soils decreases shear strength, and saturated soils are more likely to lead to slope failure. Perched water tables, groundwater seeps, and excessive precipitation are some examples of water sources that may lead to slope failure in certain conditions.

Many things can impact the stability of a slope. Just like with stream crossings, all geomorphic factors affecting slope stability should be considered when determining the risk of slope failure.
After the geomorphic factors for each slope crossing have been adequately assessed, these indicators can be fed into our geomorphic framework of slope stability to determine how likely slope failure is at a particular location.

An example of a risk matrix developed for slope stability is below. This matrix is determining the likelihood that a slope failure will occur and multiplying that by a known consequence to derive a risk factor (from the formula above). For this type of risk matrix to work, robust rational and consequence definitions should be developed to support the risk estimation. In this example, geomorphic analyses have resulted in a specific set of justifications for the likelihood of slope instability. These categories are then assigned risk factors. Very Low stability slopes, as defined by the rational in the matrix, have an Almost Certain (5) risk factor.

Detailed definitions have also been determined for the Failure at Road consequence, and those definitions are assigned risk factors. A slope failure at a road is considered Critical (5) if the road is a critical evacuation route, major transportation corridor, or restricts access to emergency facilities. Almost Certain (5) slope failures at Critical (5) roads have a Risk Factor of 25 and require mitigation.

While this example matrix only lists one consequence category (Failure at Road), a risk matrix can be designed to include as many consequences as necessary to capture the complete risk profile. Additionally, the application of five risk factors is merely an example. Risk matrices can be designed with as many or as few risk factor categories as necessary.

The outcome of this analysis is a set of risk factors that pipeline operators, city planners, engineers, or transportation officials can use to prioritize capital spending in a non-biased way, proactively estimate capital budget, manage interim risks, and more accurately estimate maintenance budgets.

[i] https://www.minneapolisparks.org/_asset/hwlxv3/west_river_parkway_faq.pdf
Photo: http://www.windomdam.com/CSS/2008-11-18%20Letter%20to%20City%20Responding%20to%20the%20SEH%20Feasibility%20Report.htm

The Roundabout Craze

Andrew Plowman, Transportation Project Manager, WSB

Roundabouts have been used throughout Europe and Australia for decades but have only gained popularity in the United States in the past 20 years. There are currently more than 3,500 roundabouts in the United States. Minnesota has also joined the roundabout craze, with more than 140 roundabouts built as of 2014, and upward of 20 additional roundabouts built each year.

Some jurisdictions, such as the New York State Department of Transportation and the City of Bend, Oregon, have implemented a “roundabouts first” policy. These policies require that a roundabout be analyzed and, if feasible, should be the preferred option.

To understand why roundabouts have become so popular, it is important to understand what a roundabout is and why roundabouts perform so well compared to other intersection alternatives.

What is a roundabout?
A roundabout is a type of intersection that includes a circular central island and lane(s) traveling around the central island in a counterclockwise direction. A roundabout is different from traffic circles and rotaries.

There are four main differences between rotaries/traffic circles and modern roundabouts:

Right of way

In a roundabout, vehicles already within the circle have the right of way.
In a rotary or traffic circle, entering vehicles have the right of way.

Size

Roundabouts are comparatively smaller (typically 80-180 feet in diameter).
Rotaries and traffic circles can be as big as 300-400 feet in diameter.

Changing lanes

Changing lanes within a roundabout is not allowed. Lane integrity must be maintained through to exit.
Changing lanes is allowed in rotaries and traffic circles (though sometimes this is difficult, as shown in the famous scene from National Lampoon’s European Vacation).

Deflection upon entry

Deflection is crucial to appropriate roundabout design, as it promotes lower speeds and encourages yielding.
In a rotary or traffic circle, entering traffic aims to the right of the central island, which does not promote lower speeds or yielding.

How to drive a roundabout
Roundabouts can have a variety of configurations, depending on the capacity requirements on each approach. Driving a single-lane roundabout is easier than driving a multi-lane roundabout, but the basic concept is the same. The primary concept to understand for a single-lane roundabout is this: yield to pedestrians at crosswalks and to vehicles to your left within the circulating lane.

Multi-lane roundabouts add one more step to the direction listed above: choose the appropriate lane. For example, choose the left lane if you are going left or through, and choose the right lane if you are going right or through. (Yellow line: left or through; Blue line: right or through)

Benefits of roundabouts
Compared to standard intersections, roundabouts offer significant benefits.

Safety: This is one of the primary reasons roundabouts have become so popular. Research shows that roundabouts reduce fatal and injury accidents by as much as 76%, due to slower speeds and the existence of fewer conflict points.
Capacity and reduced delay: Due to the continuous flow of traffic, roundabouts can handle larger volumes than signalized intersections in the same amount of time. It is a common misconception that intersections are more efficient.
Better fuel efficiency and air quality: There is less idling by vehicles in a roundabout than in an intersection where vehicles must wait through red lights. This equates to a reduction in fuel consumption and vehicle emissions.
Landscaping opportunities: The central island of a roundabout is a great place to provide landscaping and can serve as a gateway to a community or district.
Safety for pedestrians: This is another common misconception about roundabouts. It is often thought that because a pedestrian crossing at a roundabout is uncontrolled, that it is not as safe as a signalized crossing. The figures below illustrate why the roundabout crossing is safer than crossings in standard intersections.

Roundabouts are being implemented in communities throughout Minnesota and continue to score well on many federal grant programs. We continue to stress the importance of educating drivers about how to properly navigate a roundabout, through ongoing communication with the public across multiple platforms.

Robert’s Rules of Order

By John Powell

Robert’s Rules of Order were first published in 1876 and were named for Colonel Henry Martyn Robert, a military engineer in the United States Army. Robert developed the rules after being asked to conduct a meeting at his church. Due to his inexperience in this role and no shared understanding among the attendees as to how a meeting should be conducted, the outcome was unproductive and disappointing. Robert recognized the need for a uniform understanding of parliamentary procedures and went about developing a reference document.

Robert’s Rules of Order provide a basis for the conduct of public meetings and a framework for the decision-making process. This guide to parliamentary procedures helps ensure that the rights of all participants in the process are recognized and considered. Having a set of rules to follow for decisions can be particularly useful in very contentious situations where there may be very differing and heated opinions.

How to apply Robert’s Rules of Order

The chair or other designated leader of the meeting should have a familiarity with Robert’s Rules of Order as well as any other rules specific to the organization. Even if an organization adopts Robert’s Rules of Order for the proceedings, other rules of the organization may still take precedent. While the specific rules are very detailed and extensive, in most cases conducting business first involves someone putting forth a motion for the assembly to take some sort of action. Most motions require a second, meaning another member agrees that the motion should be considered; this is to prevent a single member from consuming the assembly’s time with matters of importance only to them. Once seconded, the issue is debated and can be amended before a vote is taken.

During debate, assembly members should focus their comments and discussion on the question at hand, address their comments to the presiding officer (chair, mayor, etc.), and leave out remarks related to the personalities or motives of others. On occasion at City Council meetings, the City Attorney may be consulted to provide guidance regarding specific steps that must be taken, as they generally have the most in-depth understanding of statutes and other local rules.

Southwest LRT Groundbreaking

One of Minnesota’s largest infrastructure projects officially moves into construction.

WSB acted as West Segment Water Resources Lead for Metro Transit.

Federal, state, and local officials gathered in Hopkins to break ground on the Southwest LRT project in late November. The $2.003 billion project will be the largest infrastructure project in the state’s history and is expected to create 7,500 construction jobs, with an estimated $350 million payroll.

Our Water Resources and Environmental Compliance teams assisted Metro Transit as the West Segment Water Resources Lead. We completed the erosion and sediment control design, storm sewer design, permitting, bridge and wall drainage work. Our team was also responsible for identifying and designing Best Management Practices (BMPs) to meet permitting requirements and designed the storm sewer infrastructure that will connect existing municipal and Minnesota Department of Transportation (MnDOT) systems to one another. Additionally, we prepared water resources-related documents, including preparing plans and specifications, quantifying wetland and floodplain impacts, completed hydraulic analysis for risk assessments and performed water quality analysis of the proposed BMPs.