Freshwater Resources Monitoring ​

Surface Water Quality Summary Report 2018-2019

Milwaukee Metropolitan Sewerage District

Freshwater Resources Monitoring Program

The Freshwater Resources Monitoring group conducts routine surface water monitoring at nearly 100 fixed monitoring sites within the MMSD Planning Area. Field measurements and grab samples are taken 1-2 times per month at these sites and brought to the in-house certified laboratory for analysis. Up to 41 different parameters are sampled at each site, totaling over 60,000 data points each year. ​

Click on the sites on the map to view a site photo.

Introduction

To summarize the large amount of data collected each year, the Freshwater Resources Monitoring group produces an annual report, focusing on a specific subset of parameters and/or sites. This report focuses on water quality in 2018 and 2019 for total phosphorus (TP), total suspended solids (TSS), fecal coliform (FC) and chloride for routine monitoring data. These parameters of interest are aligned with current projects MMSD is involved in to support the work of our partners.  ​

Check out the last section of this report to learn more about these projects!​

In addition, 2018 and 2019 were two of the three wettest years on record, so this report takes a deeper look into the effects of precipitation and runoff on water quality. Because of this special topic, surveys that take place entirely outside the Milwaukee Harbor breakwater were removed as they are not included in this report. 

Results Overview

The tables show the percent of samples meeting water quality criteria for all sites in 2018 and 2019. When possible, Wisconsin 2020 Consolidated Assessment and Listing Methodology (WisCALM) guidance and criteria found in WI Administrative Code Chapters NR 102 1  (TP and FC), 104 3  (FC) , 105  4 (chloride) and the Milwaukee River Basin Total Maximum Daily Load 2  (TSS) were used.​

Scroll and click on the maps below to view the water quality results for grouped sampling sites.

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Milwaukee River Watershed Results

The Milwaukee River is the largest river within the District's service area. The Freshwater Resources Monitoring group monitors five sampling sites located along its mainstem (sites labelled RI) and creeks tributary to the Milwaukee River (Cedar Creek (CC), Indian Creek (IC), Southbranch Creek (SB), and Lincoln Creek (LC). Additionally, Fish Creek (FC), which directly drains to Lake Michigan, is also monitored.  ​

Overall, the sites in this area show varied results. None of the sites are meeting criteria for all four parameters in more than 75% of samples. However, all sites are meeting the standard for chloride greater than 75% of the time. Alternatively, no sites have greater than 75% of samples meeting criteria for TP or for FC. TSS results show half the sites are meeting the TSS criterion more than 75% of the time.​

Click on the map to view the summary results.

Menomonee River Watershed Results

The Menomonee River watershed covers 136 square miles and is nearly 28 miles in length. Approximately 90% of the watershed is within the District’s sewer service area. Six sites are sampled along its mainstem (sites labelled RI). Sites along the following tributaries to the Menomonee River are also monitored: Little Menomonee River (ML), Honey Creek (HC), and Underwood Creek (UC).​

At six of the sampling sites, TSS is meeting criteria more than 75% of the time . All sites except HC-02 and HC-03 are meeting the chloride criterion more than 75% of the time. RI-09 is the only site meeting the criteria for TP and FC in over 75% of samples. ​

Click on the map to view the summary results.

Kinnickinnic River Watershed Results

The Kinnickinnic River is located entirely in Milwaukee County and is approximately 8 miles long. Three sites are along the Kinnickinnic mainstem (RI-12, 13, 34), while two sites listed within the Kinnickinnic  River watershed are technically tributaries to the Kinnickinnic River. Site RI-33 is located on the 43rd St. ditch while site RI-35 is located on Wilson Park Creek.​

All sites are doing well for TSS and meeting the criterion more than 75% of the time. All sites are meeting FC criteria in less than 75% of samples. Site RI-35 is the only site meeting the TP criterion more than 75% of the time while site RI-33 is only meeting the criterion 3% of the time and site RI-34 is not meeting the TP criterion at all (0%). All sites are meeting the chloride criterion in greater than 75% of samples except RI-33.​

Click on the map to view the summary results.

Estuary Results

The Milwaukee Harbor Estuary encompasses the Milwaukee River below the former North Ave. dam, the Menomonee River below the Falk Corporation dam, and the Kinnickinnic River below the Chase Ave. bridge out to the breakwater. In simpler terms, it is the area where the three rivers meet and mix with Lake Michigan water. For the purposes of this report, the eastern boundary of the estuary is the Hoan Bridge.​

The FC criterion was met by most sites greater than 75% of the time. The chloride criterion was met by nearly all sites 100% of the time. Eight out of these 11 sites met the TP criterion more than 75% of the time. Within the estuary, TSS did not do quite as well as the other three parameters; only five of 11 sites met criteria more than 75% of the time.  ​

Click on the map to view the summary results.

Oak Creek/Root River Results

Oak Creek (OC) is 13 miles long and the watershed covers a 28 square-mile area located entirely within Milwaukee County. The Root River (RR) watershed is located within 4 counties (Kenosha, Milwaukee, Racine, and Waukesha) and drains a 198 square-mile area.​

No sites within the OC/RR watersheds meet the criterion for FC in greater than 50% of samples, with site RR-02 only meeting the FC criterion 11% of the time. All sites meet the chloride criterion. Only one site is meeting the TP criterion (OC-01) greater than 75% of the time. Only four of these 13 sites met TSS criteria in greater than 75% of samples.​

Click on the map to view the summary results.

Outer Harbor Results

Within the context of this report, the outer harbor is defined as the area from under the Hoan Bridge out to the breakwater of Lake Michigan, including the breakwater gaps.​

All sites are classified as meeting the criteria for all four parameters in more than 75% of samples. Sites OH-09, 10, and 11 are meeting the criteria 100% of the time for all four parameters. ​

Click on the map to view the summary results.

Footnote:

 1  Wis. Admin. Code § NR 102.06 (2020)

 2  CDM Smith. 2018. Total Maximum Daily Loads for Total Phosphorus, Total Suspended Solids, and Fecal Coliform Milwaukee River Basin, Wisconsin. Final Report. USEPA Region 5, March 19, 2018. 147 p

 3  Wis. Admin. Code § NR 104.06 (2020) The fecal coliform standard is based on a geometric mean of 5 or more samples per month, but for the purposes of this report, the criterion is used as a benchmark for water quality

 4 Wis. Admin. Code § NR 105.06 (2010)

Precipitation in 2018-2019

2018 and 2019 were exceptionally wet years; two of the wettest on record (records start in 1895). The wettest year on record in the Milwaukee area was 2019, and 2018 was the third wettest (1993 was the second wettest). Both years topped 45 inches of precipitation, which is considerably wetter than the 30-year (1981-2010) average of 34.76 inches. ​

The water quality parameters this report focuses on (total suspended solids, total phosphorus, chloride and fecal coliform bacteria) are all suspected to be affected by increased precipitation. The relationship between these parameters and precipitation and runoff are examined more closely.

2018 and 2019 were extremely wet years, but that alone does not mean that this wet weather was reflected in our sampling surveys. The histogram below shows the number of survey days that occurred at each level of precipitation.

Upon further examination, it is clear that our survey days reflect the wet conditions present in 2018-2019. There were a total of 118 survey days over these two years and 59 (50%) were wet. Additionally, 12 (10%) survey days had precipitation over 1.5 inches. However, it should be noted that 10 of the 12 targeted monitoring surveys not included in this report are some of the largest precipitation events sampled in these two years. 

For the purposes of this report, “wet” means the presence of a precipitation event over 0.1 inches within 48 hours before the survey day. Precipitation events shown here end once there is a dry period of 24 hours or more. Otherwise rainfall amounts are cut off at 13:00 the day of the survey. 

According to the USEPA: “Stream flow, or discharge, is the volume of water that moves over a designated point over a fixed period of time. It is often expressed as cubic feet per second (ft3/sec). The flow of a stream is directly related to the amount of water moving off the watershed into the stream channel.” Runoff, which is created by wet weather, is one of the major components that make up stream flow. When storms are in the area, runoff makes up a larger percentage of the total flow and when there are dry periods with little or no precipitation, runoff makes up a smaller percentage of the total flow.  https://archive.epa.gov/water/archive/web/html/vms51.html ​.

Although weather is the driver for creating runoff, ground conditions also impact the amount of runoff reaching the stream. Runoff occurs when there is more water on the ground than can be readily absorbed by the underlying soil. This water typically flows downhill over land until it joins with a body of water like a river. As this water flows overland, it is able to pick up various substances in its path like oils, fertilizers, salts, and bacteria. Runoff often has a sizeable impact on water quality. One of the biggest advantages of studying runoff is that it can account for multiple water sources including direct precipitation. It accounts for water from melting snow or ice, human inputs, and delayed effects of precipitation that happened further upstream instead of at the study site. ​

For this report, percentage of flow as runoff values were determined with the ratio of runoff to total flow. Daily mean flow data collected by the USGS were separated into three components: total flow, direct runoff, and base flow, using the Local Minimum Method on the Web-based Hydrograph Analysis Tool (WHAT).

Comparison of Wet and Dry Stream

Wet stream on the left, dry stream on the right.

Sensitivity to Wet Weather

The eight plots in the following section are of selected sites that represent four categories found in MMSD’s monitoring area: urbanized creek with concrete-lined channel, naturalized creek outside of heavy urbanization, river system, and estuary where the rivers mix with Lake Michigan. This illustrates how sensitive each category of waterbody is to precipitation and runoff events.

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Urban Creek

Precipitation vs. Concentration

Urbanized creeks are generally in watersheds that contain large amounts of impervious surfaces that quickly convey water to the streams. The faster the water is able to make it to the creek, the less time there is for contaminants to be filtered out by vegetation or soil. Concrete-lined channels are usually very straight and can lead to faster stream velocities than a more natural stream. This high energy water is capable of picking up more contaminants and washing them downstream.​

The plots show four parameters associated with rainfall, and whether they meet water quality criteria at different amounts of precipitation. Each point represents a day this site was sampled in 2018-2019. 

  • Criteria exceedances can happen at any amount of precipitation, but once precipitation passes the green line, the creek no longer meets criteria. 
  • FC and TP appear to be the most affected by precipitation at this site, as even a small amount of rain (0.2 inches) stops criteria from being met.
  • Chloride is a different case due to the heavy influence of winter road salt. For this reason, exceedances are concentrated in the winter months where there is little liquid precipitation.

Urban Creek

Runoff vs. Concentration

The plots show four parameters associated with runoff at a representative concrete-lined, urbanized creek site, and whether they meet water quality criteria at different percentages of flow made up by runoff. Each point represents a day this site was sampled in 2018-2019. 

  • The plots show a wide spread of data with no obvious pattern of when concentrations in the creek will exceed criteria. It is possible for criteria exceedances to happen at almost any runoff percentage. 
  • One pattern that is evident, especially for FC and TP, is highlighted with a vertical green dotted line. At around 30% runoff, the creek no longer meets criteria. In other words, for every sampling date where the total stream flow was made up by 30% or more runoff, the creek exceeded criteria. 
  • Chloride is a unique case because it is so closely tied with winter deicing activities in SE Wisconsin. Deicing events are typically in the winter months when liquid precipitation and runoff are very low. This leads to the points exceeding criteria being clustered on the low end of percent of flow as runoff. 
  • TSS are closely related to the high energy water that keeps the particles suspended in the water.

Naturalized Creek

Precipitation vs. Concentration

This site is typical for a creek in a more natural state. A more natural creek has a watershed that contains less impervious surfaces that quickly convey water to the streams. Slowing the speed of runoff allows more water to infiltrate into the soil and increases the amount of contaminants that are filtered out by vegetation and soil. These creeks can have large increases in the amount of water flowing in them during storms, but changes are more gradual. Natural meanders can help slow down water to avoid washing additional contaminants into the water.

The plots show four parameters associated with rainfall, and whether they meet water quality criteria at different amounts of precipitation. Each point represents a day this site was sampled in 2018-2019. 

  • Criteria exceedances can happen at any amount of precipitation, but once precipitation passes the green line, the creek no longer meets criteria.
  • FC and TP are the most affected by precipitation at this site, although criteria may still be met at much higher amounts of rainfall than in an urbanized stream. 
  • TSS has few exceedances, and chloride has none. This is reflective of the greater filtration and buffering ability of the surrounding land.

  

Naturalized Creek

Runoff vs. Concentration

The plots show four parameters associated with runoff at a representative naturalized creek site, and whether they meet water quality criteria at different percentages of flow made up by runoff. Each point represents a day this site was sampled in 2018-2019. 

  • The plots show a wide spread of data with no obvious pattern to when the water in the stream will exceed criteria . It is possible for criteria exceedances to happen at almost any runoff percentage. 
  • One pattern that is evident, especially for FC and TP, is highlighted with a vertical green dotted line. At around 50% runoff, the creek no longer meets criteria. In other words, for every sampling date where the total stream flow was made up by 50% or more runoff, the creek exceeded criteria. 
  • Chloride is a unique case because it is so closely tied with winter deicing activities in SE Wisconsin. Deicing events are typically in the winter months when liquid precipitation and runoff are very low. Chloride has no exceedances, reflective of the increased buffering and filtration of the surrounding land.
  • Total suspended solids are closely related to the high energy water that keeps the particles suspended in the water. A more natural creek like this one will generally have less exceedances than an urbanized creek.

River

Precipitation vs. Concentration

This river site can be considered a bigger version of a naturalized creek. It has a watershed that contains fewer impervious surfaces that quickly convey rainwater to the streams. Slowing the speed of runoff allows more water to infiltrate into the soil and increases the amount of contaminants that are filtered out by vegetation and soil. Rivers can have increases in the amount of water flowing in them during storms, but changes are much more gradual. Natural meanders, vegetation, other natural attributes can help slow down water to avoid washing  additional contaminants into the river.​

The plots show four parameters associated with rainfall, and whether they meet water quality criteria at different amounts of precipitation. Each point represents a day this site was sampled in 2018-2019. 

  • The plots show a wide spread of data with no obvious pattern to when the water in the river will exceed criteria. It is possible for criteria exceedances to happen at almost any amount of precipitation, but once precipitation passes the green line, the river no longer meets criteria.
  • FC, TP and TSS are the most affected by precipitation at this site, although criteria may still be met at much higher amounts of rainfall than in an urbanized creek. 
  • Chloride has no exceedances, reflective of the increased buffering and filtration of the surrounding land and increased volume of water present at a river site.

River

Runoff vs. Concentration

The plots show four parameters associated with runoff at a representative river site, and whether they meet water quality criteria at different percentages of flow made up by runoff. Each point represents a day this site was sampled in 2018-2019.  

  • The plots show a wide spread of data with no obvious pattern to when the water in the stream will exceed criteria. It is possible for criteria exceedances to happen at almost any runoff percentage. 
  • One pattern that is evident, especially for FC and TP, is highlighted with a vertical green dotted line. At around 50% runoff, the river no longer meets criteria. In other words, for every sampling date where the total stream flow was made up by 50% or more runoff, the river exceeded criteria.
  • Chloride is a unique case because it is so closely tied with winter deicing activities in SE Wisconsin. Deicing events are typically in the winter months when liquid precipitation and runoff are very low. Chloride has no exceedances, reflective of the increased buffering and filtration of the surrounding land and increased volume of water present at a river site.
  • TSS are closely related to the high energy water that keeps the particles suspended in the water. The sampling dates that exceed criteria for TSS are concentrated toward the higher values of percent of flow as runoff. Flows get faster and more turbulent as the amount of runoff increases.

Estuary

Precipitation vs. Concentration

The Milwaukee Estuary is a complex area where three major rivers join together and also interact with Lake Michigan. The estuary is located in downtown Milwaukee where there are significant amounts of impervious surfaces. This area is dredged to keep it artificially deeper which greatly slows down stream velocity. To add to the complicated nature of the estuary, Lake Michigan water is constantly moving in and out of the area and mixes with the river water coming downstream. Increases in flow in the estuary are less noticeable than further upstream and at times can almost appear stagnant. The large volume of water in the estuary is the main driver for slowing stream velocity. The flow increases may also be delayed by days after rainfall happens far upstream.​

The plots show four parameters associated with rainfall, and whether they meet water quality criteria at different amounts of precipitation. Each point represents a day this site was sampled in 2018-2019.

  • The plots show a wide spread of data with no obvious pattern to when the water in the stream will exceed criteria. Criteria exceedances can happen at any amount of precipitation, but once precipitation passes the green line, the waterbody no longer meets criteria.
  • FC is most affected by precipitation at this site, although criteria may still be met at much higher amounts of rainfall than in all other site types. 
  • Chloride has few exceedances outside of directly during winter deicing events, likely due to the large volumes of water present as well as influence from Lake Michigan. 
  • TSS shows no clear pattern, which is reflective of the high complexity of the Milwaukee Estuary system.

Estuary

Runoff vs Concentration

The plots show four parameters associated with runoff at a representative estuary site, and whether they meet water quality criteria at different percentages of flow made up by runoff. Each point represents a day this site was sampled in 2018-2019. Criteria exceedances can happen at any amount of runoff, but once precipitation passes the green line, the waterbody no longer meets criteria.

  • The plots show a wide spread of data with no obvious pattern to when the water in the stream will exceed criteria. It is possible for criteria exceedances to happen at almost any runoff percentage. 
  • One pattern that is evident, especially for FC and TP, is highlighted with a vertical green dotted line. At around 60% runoff, the stream no longer meets criteria. In other words, for every sampling date where the total stream flow was made up by 60% or more runoff, the waterbody exceeded criteria. 
  • Chloride levels can have wider ranges because the water that feeds the estuary can come from hundreds of miles upstream from numerous different sources. It is possible to exceed criteria during deicing events, but exceedances tend to be rare due to the sheer volume of water in the estuary and Lake Michigan diluting out the contaminants.
  • TSS are closely related to the high energy water that keeps the particles suspended in the water. The sampling dates that exceed criteria for TSS are concentrated toward the higher values of percent of flow as runoff. Flows get faster and more turbulent as the amount of runoff increases.

Requesting Data

MMSD has been monitoring the Milwaukee area waterways for over 40 years to document long-term beneficial water quality improvements and to help protect and manage the area’s waterways.​

Additional data can be accessed through MMSD Records Department via email request ( recordsrequest@mmsd.com ), website “Contact us” form on  mmsd.com , or in person during regular business hours. 

Data are uploaded annually to USEPA’s data warehouse and can be viewed or downloaded on the National Water Quality Monitoring Council Water Quality Portal ( https://www.waterqualitydata.us ).​

Want to know more?

Check out these websites to learn more about projects that MMSD has been involved in:

Wisconsin Department of Natural Resources Milwaukee River Basin Total Maximum Daily Load (TMDL):  https://dnr.wi.gov/topic/TMDLs/Milwaukee /

Southeastern Wisconsin Regional Planning Commission (SEWRPC) Regional Chloride Impact Study:  https://www.sewrpc.org/SEWRPC/Environment/ChlorideImpactStudy.htm 

Wet stream on the left, dry stream on the right.