HURON CREEK GEOMORPHOLOGY SURVEY

Transcription

1 HURON CREEK GEOMORPHOLOGY SURVEY Submitted By: Rachel Blink Kevin Hachey December 18, 2007 Michigan Technological University Dr. Alex Mayer Linda Kersten Huron Creek Watershed Management Plan

2 ABSTRACT The Huron Creek watershed is located in north-central Houghton County in the Upper Peninsula of Michigan. This document is a multi-part geomorphology analysis completed on Huron Creek as part of the creation of a watershed management plan. Due to land use changes and direct changes in the physical location of Huron Creek, this geomorphology study was deemed necessary to find out more information about Huron Creek and the impact of development on the creek. Several field tests were performed at various locations along the creek to serve as a baseline that can be used in later evaluations. Some of these baseline tests still need to be completed. In order to reduce the impact of development on the creek near the Copper Country Mall, the construction of a detention pond is recommended. Currently, the development along this area of the creek may have a direct effect on the detention ponds located behind Wal-mart. The development may also cause problems in the future for the Copper Country Mall parking lot. It is also recommended that some form of bank stabilization be done in this section of the creek. Another problem area is the Waterfront Park. Recommendations for the park are currently under negotiation, since this is more of a public recreation area. Finally, in order to better understand the impacts of development along the entire length of the creek, monitoring of the creek will need to be continued in the future. 1

3 TABLE OF CONTENTS 1.0 INTRODUCTION PROBLEM DEFINITION AND BACKGROUND DATA PROJECT/TASK DESCRIPTION DATA QUALITY OBJECTIVES REACH DESCRIPTIONS REACH REACH REACH REACH REACH REACH REACH MODIFIED BEHI INTRODUCTION PROCEDURE DATA COLLECTION INTERPRETATION RESULTS AND ANALYSIS STREAM HABITAT SURVEY INTRODUCTION PROCEDURE DATA COLLECTION RESULTS AND ANALYSIS CROSS SECTION AND SLOPE MEASUREMENT INTRODUCTION PROCEDURE DATA COLLECTION RESULTS AND ANALYSIS SEDIMENT MONITORING INTRODUCTION PROCEDURE DATA COLLECTION RESULTS AND ANALYSIS OTHER EROSION MONITORING INTRODUCTION PROCEDURE DATA COLLECTION RESULTS AND ANALYSIS PHOTOGRAPHS REACH REACH REACH REACH REACH RECOMMENDATIONS GEOMORPHOLOGY COMPLETION REACH 6 RECOMMENDATIONS DETENTION POND LOCATION 6-3 BANK STABILIZATION WATERFRONT PARK CONTINUED MONITORING HEAD CUT MONITORING REFERENCES 37 2

4 LIST OF TABLES TABLE 1.1: DATA QUALITY ASSURANCE CRITERIA 10 TABLE 1.2: PROPOSED GEOMORPHOLOGY SURVEY LOCATION DESCRIPTIONS 12 TABLE 2.1: BEHI SURVEY SCORES 15 TABLE 2.2: BEHI HAZARD CATEGORIES 15 TABLE 2.3: BEHI RESULTS 16 TABLE 3.1: STREAM HABITAT SURVEY 18 TABLE 4.1: SLOPE MEASUREMENTS 23 TABLE 5.1: SIEVE SIZES 25 TABLE 5.2: SEDIMENT PIN MEASUREMENTS 25 TABLE 8.1: GEOMORPHOLOGY COMPLETION SURVEYS 32 TABLE 8.2: CONTINUED MONITORING FREQUENCY RECOMMENDATIONS 35 3

5 LIST OF FIGURES FIGURE 1.1: HURON CREEK WATERSHED 6 FIGURE 1.2: 2005 HURON CREEK WATERSHED LAND USE MAP 7 FIGURE 1.3: GEOMORPHOLOGY SURVEY LOCATIONS 11 FIGURE 4.1: CROSS SECTION FIGURE 4.2: CROSS SECTION FIGURE 4.3: CROSS SECTION FIGURE 4.4: CROSS SECTION FIGURE 4.5: CROSS SECTION FIGURE 4.6: CROSS SECTION FIGURE 4.7: SLOPE MEASUREMENT DIAGRAM 23 FIGURE 5.1: GRAIN SIZE DISTRIBUTION 26 FIGURE 6.1: OTHER EROSION MONITORING LOCATIONS 28 FIGURE 7.1: LOCATION FIGURE 7.2: LOCATION FIGURE 7.3: LOCATION FIGURE 7.4: LOCATION FIGURE 7.5: LOCATION FIGURE 7.6: LOCATION FIGURE 8.1: PROPOSED DETENTION POND LOCATION 33 4

6 LIST OF APPENDICES APPENDIX A BEHI FORMS & FIELD DATA 38 APPENDIX B STREAM HABITAT FORMS & FIELD DATA 39 APPENDIX C CROSS SECTION & SLOPE FIELD DATA 40 APPENDIX D MECKLENBURG SPREADSHEET 41 APPENDIX E OTHER EROSION MONITORING PICTURES 42 APPENDIX F HYDROCAD STORM POND SIZING NOTES/ASSUMPTIONS 43 APPENDIX G WATERFRONT PARK PLANS 44 5

7 1.0 INTRODUCTION The Huron Creek watershed is an approximate 3.4 square mile watershed located in north-central Houghton County in the Upper Peninsula of Michigan (Figure 1.1). Huron Creek empties into the Portage Canal. This document is a multi-part geomorphology analysis completed on Huron Creek as part of the creation of a watershed management plan. The watershed management plan took its first step in June 2006 when the Huron Creek Advisory Council was formed and made their vision statement (Huron Creek Watershed Vision Statement 2006). The goal of the watershed management plan is to asses the current state of Huron Creek, set voluntary goals for future uses of the creek, and proposes ways to achieve those goals. Figure 1.1: Huron Creek Watershed. 6

8 1.1 PROBLEM DEFINITION AND BACKGROUND Significant land use changes have been occurring in the Huron Creek watershed over the past few decades. Between 1978 and 2005, the watershed s developed areas have increased by 15.4 percent. As of 2005, 29.8 percent of the watershed was considered to be developed (Figure 1.2). Land use changes such as these can have adverse effects on stream channel structure, amount of sediment loading, and overall stream habitat. Figure 1.2: 2005 Huron Creek Watershed land use map. 7

9 While land use effects are indirect, there have also been direct changes in the physical location of Huron Creek. The most downstream section of the creek, including the mouth, was relocated to the east when the Houghton waterfront park was created. This relocation took place at an unknown date. In 2004, a portion of the creek directly downstream of the former Huron Lake was relocated when Wal-Mart expanded to a super-center. This portion of the creek is part of an MDEQ-regulated mitigation site that is monitored by the City of Houghton. The stream channel has also been manipulated by development. It has been greatly impacted by the impermeable surfaces in its watershed causing high runoff flow rates. Also, Huron Creek is on the Further Evaluation section of the MDEQ 303d list, primarily due to water quality concerns associated with landfill leachate and commercial development upstream. This geomorphology study was deemed necessary to find out more information about Huron Creek and the impact of development on the creek. A geomorphology study is relevant in assessing erosion. This project has been designed to achieve the following overall goals: 1. Provide a baseline of geomorphologic conditions for future comparison. 2. Provide data for use in relating geomorphology with land use, hydrology and condition of stream re-route areas. 3. Provide data for use in recommending BMPs for the Huron Creek watershed management plan. 4. Provide preliminary recommendations for stream improvements as they relate to stream stability. This report is organized by chapter to deal with the major topics involved with the geomorphology study that was conducted. The rest of Section 1 introduces the project and the organization of the watershed in more detail. Sections 2 through 7 address the different field surveys that were performed. Section 8 is a compilation of recommendations that should be taken into consideration. 1.2 DATA PROJECT/TASK DESCRIPTION The Huron Creek watershed geomorphology study consists of the following survey types: Modified Bank Erosion Hazard Index (BEHI) Stream Habitat Survey Sediment Monitoring Cross-Section and Slope Measurements Other Erosion Monitoring Photos 8

10 These survey types were chosen on the basis of discussions with Michigan Department of Environmental Quality (Joe Rathbun 2007). The following is a brief description of each survey: Modified BEHI This is a method for assessing stream bank condition and erosion potential. This includes observing physical characteristics of the stream banks, assigning individual scores, and calculating an overall score that indicates risk of bank erosion. Stream Habitat Survey This is a survey that identifies channel bottom materials, streamside vegetation and channel characteristics and uses them to calculate an overall stream habitat score. Sediment Monitoring This survey characterizes sediment size distributions (<1 in diameter) and establishes sediment monitoring locations in the bed of the creek. These locations have been designed for monitoring aggradations and degradation in the creek bed. Cross Section and Slope Measurement Physical measurements of crosssections have been completed at designated locations along Huron Creek. Other Erosion Monitoring This is a visual survey that documents erosion within 200 feet of the stream banks. Locations have been recorded along with a photo. Photos Photos have been taken at designated locations for comparative purposes. Photo locations correspond with specific survey locations indicated in this document. Methods for each type of survey are described in more detail in their respective sections throughout this document DATA QUALITY OBJECTIVES The level of data quality required is such that the resulting data: Falls within a reasonable range of expected and/or previously collected data. Is reported within the number of significant digits appropriate for the measurement technique. Under similar conditions, can be easily reproduced within a reasonable range of precision. The following table describes quality assurance criteria for each geomorphology survey type: 9

11 Table 1.1: Data quality assurance criteria. Procedure Accuracy Precision Comparability Completeness Modified Bank Erosion Hazard Index (BEHI) Stream Habitat Survey Sediment Monitoring Cross-Section & Slope Measurements Other Erosion Monitoring Review of literature, example surveys & photos. Review survey form with staff prior to field data collection. Use of ASTM standard method for sieve analysis (ASTM D422-63) Field sketch of cross-section measurement to check. identification of erosion; example photos Repeat measurements by separate staff. Agree on values. Repeat measurements by separate staff. Agree on values. Collect duplicate sample at one sediment monitoring location. See comment (2) below. Complete slope measurements 2x at each location to check. Spot-checks of staff observations. - See comment (1) below. - Review number and location for appropriateness. Review number and location for appropriateness. Review number and location for appropriateness. Review number and location for appropriateness. 100% 100% 100% 100% N/A 100% Due to the observational nature of these surveys, traditionally defined accuracy and precision are difficult to assess. The following should be kept in mind when collecting and reviewing field data, and reviewing methods: 1. Stream bank conditions are naturally variable even in stable streams and to characterize a stream reach it is recommended that at least 100 of the stream reach be viewed before the BEHI observations are made. Stream banks adjacent to riffle areas tend to be the most stable section of a stream channel, while banks in meander bends tend to have the highest erosion rates even in geomorphologically stable streams. 2. The duplicate sediment size distribution graph will be compared with the one resulting from the original sample for similarity. This will be a subjective, observational comparison to see if the duplicate graph is significantly different from the original sample s graph. Cross section and slope locations were chosen based on one or several of the following criteria: The area is a straight reach between two meanders or bends The channel section and form is typical of the stream or reach There is a reasonably clear view of geomorphic features. 10

12 1.3 REACH DESCRIPTIONS For the purposes of this management plan, Huron Creek has been divided into reaches. These reaches have been chosen based on the characteristics and geography of Huron Creek to help organize the watershed. Figure 1.3 is a map showing the locations of each reach and, more specifically, the points that will be used as data collection points. These points have been determined by walking the creek to find representative areas for each reach. The locations were picked where access was less difficult, when possible. Also, places with specific problems or natural conditions were noted at this stage. Some reaches had more than one location designated for certain surveys. The reason for this is that although one location may have been representative of the reach, there may have been a specific reason for adding a survey to a different location. One example would be the need for monitoring sedimentation at a specific location. Figure 1.3: Geomorphology survey locations. 11

13 Table 1.2 below describes what surveys will be carried out at each point indicated in Figure 1.3. Table 1.2: Proposed geomorphology survey location descriptions. Location Name Survey Type(s) "Other Monitoring" 1-2 BEHI, HABITAT, X-SECTION & SLOPE, SEDIMENT STONE WALL, CULVERTS 2-1 SEDIMENT (SIEVE ONLY) MONITOR CONCRETE BANKS 2-4 BEHI, HABITAT, X-SECTION & SLOPE, SEDIMENT 3-3 BEHI, HABITAT, X-SECTION & SLOPE, SEDIMENT CULVERTS, OTHER EROSION/RUNOFF PROBLEMS 4-3 BEHI, HABITAT, X-SECTION & SLOPE UNSTABILIZED SLOPES, CULVERTS 5-2 BEHI, HABITAT, X-SECTION & SLOPE 6-1 BEHI, HABITAT, X-SECTION & SLOPE 6-2 BEHI, HABITAT BEHI, HABITAT, X-SECTION 6-3 & SLOPE BEHI, HABITAT, X-SECTION 7-1 & SLOPE REACH 1 Reach 1 stretches from the mouth of the creek to the Houghton Canal Road crossing. This reach has very good access along its entire course and is highlighted by the Houghton waterfront park. In general, the channel is very straight and has little vegetation REACH 2 Reach 2 is the stream bound by Houghton Canal Road and M-26. This reach consists of a lot of step pools throughout. Also, there is a more natural look to the reach than most of the others, as it is in a wooded valley and has little noticeable development REACH 3 Reach 3 goes from the M-26 crossing upstream to Sharon Ave. This reach has a mix of riffles, runs, and pools. There is a waterfall in this section about 5 feet high. A good portion of this reach is not very accessible, and there are parts that are directly impacted by development. There are some banks that have concrete lining in this reach, and the waterfall is what is left of an old dam. The vegetation varies from dense to sparse throughout this reach, but in general there is sufficient cover. 12

14 1.3.4 REACH 4 Reach 4 is the section from Sharon Ave. to the falls nicknamed Wal-mart Falls east of Ridge Rd. This reach cuts through the middle of developed areas and receives considerable storm water along creek inlets from the numerous parking lots. There are many areas where it is obvious the channel diverts itself in high flow conditions. A fair portion of this reach is not very well vegetated REACH 5 Reach 5 is a meadow-like stretch of creek behind Wal-mart. This reach is the stream located between Wal-mart Falls and the wetlands behind Wal-mart. At the moment, this reach is more or less an open field with some high grass in areas. This section of the creek is new, as the water was diverted here when Wal-mart was built REACH 6 Reach 6 is a tributary creek that runs from Copper Country Mall downstream to the detention ponds located behind Wal-mart that drain into Huron Creek. This reach is perhaps the most heavily impacted by development, as it receives runoff from the Copper Country Mall and the area surrounding Festival Foods REACH 7 Reach 7 is the natural or reference reach and is located upstream from Green Acres Rd. This is also the headwaters of Huron Creek. As the headwaters, the creek is smaller in this reach and is very brushy along its length. This reach is considered virtually untouched and is being used to compare the creek s developed areas to its natural conditions. 13

15 2.0 MODIFIED BEHI 2.1 INTRODUCTION The Bank Erosion Hazard Index (BEHI), created by Dave Rosgen of Wildland Hydrology, Inc. (Rosgen, 2001), is one of several procedures for assessing stream bank erosion condition and potential. It assigns point values for several aspects of bank condition and provides an overall score characterizing erosion risk. This method will be used to inventory stream bank condition over large areas and prioritize eroding banks for remedial actions, such as those to be included in the Huron Creek watershed management plan. This report describes the modified BEHI method only, as the method to be used by MTU/CWS in the Huron Creek watershed. 2.2 PROCEDURE The procedure described below is the modified BEHI which is only different from the regular BEHI in that it does not require identification of bankfull indicators. The scoring method described below is also modified in that the step of calculating BEHI scores has been simplified such that there is only a single score for each metric, rather than the range of possible scores provided in Rosgen s original paper. This simplification is intended to remove some unnecessary subjectivity from the field observations, without overly reducing the utility of the procedure. Materials needed for completion of modified BEHI: 1. Yard stick or tape for measuring root depth, bank height 2. BEHI scoring forms (see Appendix A), pencil & clipboard 3. Map indicating monitoring locations 4. GPS 5. Camera The modified BEHI consists of the measurement of four metrics: 1. Ratio of root depth to bank height 2. Root density, in percent 3. Bank angle, in degrees 4. Surface protection, in percent Ratio of root depth to bank height: Root depth is the ratio of the average plant root depth to the bank height, expressed as a fraction (e.g. roots extending 2 into a 4 tall bank = 0.50). Root density: Root density, expressed as a percent, is the proportion of the stream bank surface covered (and protected) by plant roots (e.g. a bank whose slope is half covered with roots = 50%). Surface protection: Surface protection is the percentage of the stream bank covered (and therefore protected) by plant roots, downed logs and branches, rocks, etc. In many streams in southern Michigan, surface protection and root density are synonymous. 14

16 Bank angle: Bank angle is the angle of the lower bank the bank from the waterline at base flow to the top of the bank, as opposed to benches that are higher on the floodplain. Bank angles greater than 90º occur on undercut banks. For bank angle measurements in the Huron Creek watershed, visual estimates were used. 2.3 DATA COLLECTION The modified BEHI was completed at the locations shown on Figure 1.3 and as indicated in Table 1.2. Locations were chosen to be representative of identified reaches. Data collection was completed after a sufficient length of the reach was examined (at least 100 ), so that representative conditions could be identified. Conditions on both banks were assessed, and scored separately if they were consistently different. The BEHI assessment was typically done from the waterline at base flow to the height at which peak flow may occur. 2.4 INTERPRETATION Overall scores for the modified BEHI are calculated by summing the scores for each individual metric using the values in Table 2.1 below. The overall BEHI score corresponds to an erosion hazard category. It should be noted that the overall BEHI scores and categories were created by Rosgen s work in the Rocky Mountain States, and in the future these may be modified for conditions in Michigan. Table 2.1 shows each test and individual test score for the modified BEHI. Table 2.2 shows the resulting BEHI hazard categories after the score for each category has been totaled. Root Depth Values Root Depth Scores Root Density (%) Table 2.1: BEHI survey scores. Root Density Scores Surface Protection (Avg %) Surface Protection Scores Bank Angle (degrees) Bank Angle Scores < 5 10 < 5 10 < > Table 2.2: BEHI hazard categories. BEHI Hazard Category Total Score By Category Very Low 5.8 Low Moderate High Very High Extreme

17 Once all locations were assigned a total Hazard Index score, the data was used to compare risk between locations and identify priority areas (areas of concern) for the watershed management plan. It also identified areas to be monitored in the future. Comparison of values was facilitated by using graphs or comparing data spatially using GIS. 2.5 RESULTS AND ANALYSIS The following table summarizes the total scores for each monitoring location: Table 2.3: BEHI results. Monitoring Modified BEHI BEHI Hazard Location Score Category Moderate Low 3-3 West Bank 8.8 Low 3-3 East Bank 13.8 Moderate Low Low Low High High Very Low Two BEHI assessments were made at location 3-3 because there was a drastic difference between the east and west banks. A high BEHI category represents stream banks that are highly susceptible to erosion. The majority of the BEHI hazard categories for Huron Creek are moderate to low. However, locations 6-2 and 6-3 had high scores. It is clear that this reach has the most erosion problems, especially when compared with the other locations. Recommendations for this reach can be found in Section 8.2. Although monitoring location 1-2 received a moderate hazard score, the entire reach would not necessarily receive this score. The location chosen was very specific, and was a good average of Reach 1. However, there are some locations within Reach 1 that would receive a much higher hazard score. Some of the banks have experienced serious erosion problems just within the last three months. For this reason and others (including aesthetics and safety), recommendations for Reach 1 (the Waterfront Park) are currently under negotiation. Recommendations for the Waterfront Park can be found in Section 8.3. Full BEHI assessment tables for each monitoring location are located in Appendix A. 16

18 3.0 STREAM HABITAT SURVEY 3.1 INTRODUCTION This stream habitat survey is designed for simple documentation of channel, flow and bank characteristics through visual observation. The characteristics observed are those that most influence fish and/or macroinvertebrate habitat quality. Examples of these include channel bottom materials, stream meanders, bank slope and bank vegetation. The data collection form used for this survey was created by Joan Chadde at the Western Upper Peninsula Center for Science, Math and Environmental Education (Michigan Technological University), and was adapted from the U.S. Forest Service Stream Reach Inventory and Channel Stability Evaluation (1978). 3.2 PROCEDURE Materials needed for completing the habitat survey: 1. Habitat Survey Form, clipboard, pencil 2. Map of monitoring locations/gps coordinates 3. Camera 4. GPS The Stream Habitat Survey Form (Appendix B) was used in the field to acquire information about the health of the stream habitat. All personnel completing data collection familiarized themselves with the form and its terminology prior to use. The survey was completed by reading each parameter question and checking the box that most closely corresponds to the condition of the stream. Each box is associated with a point score, which is entered in the last column on the form. Once all ten parameters are scored, the total of those scores is the total stream habitat score for that stream reach (see Table 3.1). Habitat quality is ranked according to the following: 0 15 = POOR = FAIR = GOOD = EXCELLENT Note: For parameter #1 This is good to excellent (flows year-round) for most parts of the creek. Some locations in the creek re-route area near Wal-Mart do dry up, but only during drought/dry season conditions. 3.3 DATA COLLECTION The Huron Creek habitat survey was completed at the locations indicated in Table 1.2 and shown on Figure 1.3. Locations were chosen to be representative of identified reaches. One total habitat score was determined for each reach, with the exception of Reach 6, as it is most impacted by development and is a big concern. Data collection was only completed after a sufficient length of the reach had been examined (at least 100 ), so that representative conditions were identified. Conditions on both banks were 17

19 assessed, and scored separately if they were consistently different. In addition to completing the field data sheet, a photo and GPS coordinates were taken at each monitoring location/reach. 3.4 RESULTS AND ANALYSIS The following table summarizes the total scores for each location: Table 3.1: Stream habitat survey Total Station Points Category Fair Good Fair Good Good Good Fair Fair Excellent Table 3.1 shows the results of the Stream Habitat Survey for each reach of Huron Creek. Completed survey forms can be found in Appendix B. As shown in Table 3.1, there are four scores that had a score of Fair. Stations 1-2 and 3-3 received those scores because they had significant bank erosion, a lack of curves or bends, and a lack of pools, riffles, and runs. Stations 6-2 and 6-3 were Fair because they had a lack of curves or bends, significant bank erosion, and particularly steep slopes. 18

20 4.0 CROSS SECTION AND SLOPE MEASUREMENT 4.1 INTRODUCTION Stream channel cross-sections are used for measurement and documentation of channel shape, location and size. Often measurements are made repeatedly over time to observe how much and in what ways the channel changes. Cross-section locations are often monumental in being used as monitoring locations for other parameters so that multiple types of data can be compared and/or correlated with the cross-section data. The Cross-section survey consists of placing endpoints that are marked with permanent monuments, stretching a tape between them and measuring downwards to the bank and channel bottom. Channel slope was also measured using simple surveying equipment. Slope data is useful for flow and sediment transport calculations and for hydrologic modeling. 4.2 PROCEDURE Materials needed for cross-section and slope measurements: 1. 4 x ½ rebar sections (2 for each cross-section location) 2. Map of cross-section locations 3. Level (regular construction-type level) 4. Tape / Tape measure (at least 50 long) 5. Surveying level & tripod 6. Surveying rod 7. Colored survey ribbon 8. Cross-Section and Slope Documentation Sheet, clipboard, pencil 9. GPS 10. Camera First, the permanent markers for endpoints were established by driving a 4 x ½ piece of rebar vertically into each bank to mark endpoints leaving approximately 6 above the surface (see Figure 1.3 for cross-section locations). Colored plastic caps were attached to the top of each rebar for identification. Colored tape was wrapped around the rebar where the tape was level when stretched between the two pieces of rebar. It was checked to make sure that: 1. The two pieces of rebar formed a line that was perpendicular to the centerline of the stream at that location. (This was eyeballed.) 2. The cross-section location was established in a location representative of the stream reach. 3. The endpoint locations were sufficiently far enough apart to characterize the channel, banks and floodplain. The location of each endpoint was documented with a GPS and recorded on the field sheet (see Appendix C). 19

21 The zero end of the tape was attached to the left stake (when facing north or downstream). The tape was stretched tight and level above the water from the left stake to the opposite endpoint of the cross-section. A carpenter s level was used to ensure that the tape was actually level. Spring-clamps were used to hold the tape in place. The total distance between endpoints was recorded on the field form provided (see Appendix C). Starting with the left endpoint stake as zero, the distance from the tape to the creek bed or ground surface was measured using the surveying rod. The tops of isolated boulders and logs were avoided. The measurements were taken at appropriate intervals for the point being measured (2 maximum). The measurements were taken on slope breaks, the edge of the water, floodplain boundaries, and other features that assisted in depicting the characteristics of the stream. The measurements were continued across the channel to the right endpoint stake. The horizontal distance was measured to 0.1 ft. Vertical distances were recorded to 0.01 ft. Finally, a complete sketch of the cross section was completed using the Mecklenburg Spreadsheet (see Appendix D). For the slope measurement, one person with a surveying rod moved upstream from the cross-section far enough to adequately characterize the slope in the reach/ area of the cross-section. The rod was held at a location where the elevation on the rod was visible from a surveying level at the cross-section location. The surveying level was set up as close to the stream as possible. The distance from the rod to the level was then measured with a tape to the nearest foot. A height reading was then read off of the rod and documented to the nearest 0.01 ft. This process was done for two points upstream and two points downstream (when possible) for each cross section location. The channel slope was calculated with the following formula: ABS [Upstream Height Downstream Height] X 100 = Slope (%) Distance between Upstream and Downstream Points Absolute value of the height measurements was used because surveying rods are made with values increasing from top to bottom or bottom to top. 4.3 DATA COLLECTION Cross-section and slope measurements were completed at the locations shown on Figure 1.3 and as indicated in Table RESULTS AND ANALYSIS Figures 4.1 through 4.6 are the cross sections for the locations that were measured. 20

22 Figure 4.1: Cross section 3-3. Figure 4.2: Cross section 4-3. Figure 4.3: Cross section

23 Figure 4.4: Cross section 6-1. Figure 4.5: Cross section 6-2. Figure 4.6: Cross section 7-1. These cross sections are useful in determining a baseline in order to monitor bank erosion in the future. Section 8.4 discusses the frequency of these future measurements. 22

24 Four different slope calculations were performed. This can be helpful in determining the longitudinal profile of the measurement location. Figure 4.7 shows which slope measurement corresponds to which location along the section that was measured. The cross section measurement point is marked with an X. Figure 4.7: Slope measurement diagram. Slope 1 is usually roughly from feet downstream, slope 2 is roughly from 50 feet upstream to 50 feet downstream, slope 3 is roughly from feet upstream, and slope 4 is roughly from 100 feet downstream to 100 feet upstream. These distances are not consistent for each location, but are rough measurement locations. The actual GPS coordinates can be found in Appendix C. Results from the slope measurements are summarized below: Table 4.1: Slope measurements. Location Slope 1 Slope 2 Slope 3 Slope 4 % % % % Slopes at Locations 1-2 and 2-4 still need to be completed. Due to excessive vegetation at Locations 6-3 and 7-1, only one slope was measured. The slope at Location 6-3 was measured from 96 feet downstream to 40 feet upstream of the cross section location. The slope at Location 7-1 was measured from 39 feet downstream to 50 feet upstream of the cross section location. The highest slope measurement was in Reach 6. These slope measurements do not necessarily correspond with bank erosion, since they are longitudinal slopes. They may be more useful in monitoring problems associated with high flows. Recommendations for longitudinal slope measurements are discussed more in Section

25 5.0 SEDIMENT MONITORING 5.1 INTRODUCTION The composition of stream bed and banks is an important facet of stream character, influencing channel form and hydraulics, erosion rates, sediment supply, and other parameters1. Sediment monitoring of Huron creek was be completed to identify baseline characteristics of the bed and banks as well as to evaluate locations of suspected excessive deposition. 5.2 PROCEDURE Materials needed for sediment monitoring: 1. Field notebook, pencil 2. Yard stick or other rigid measuring device 3. GPS 4. One ½ x 24 length of rebar for each sampling site 5. Hammer/sledge 6. Shovel 7. One 1-gal ziplock bag for each sampling site 8. Permanent Marker to label bags Sediment Pins At the locations indicated in Figure 1.3, ½ x 24 lengths of rebar were driven into the center of the stream channel, leaving at least 10 of rebar above the surface of the bed material. The rebar was driven in securely and is not susceptible to tipping. If the rebar could not be driven into the bed a sufficient distance, the bar was relocated as close as possible up or downstream where it could be securely placed. In a field book, the the date, time and weather conditions were recorded, as well as the testing location. Using a yard stick or other rigid measuring device, the distance from the top of the rebar to the surface of the bed material was measured and recorded in the field book. These measurements are useful in determining sediment deposition at the location being measured. The measurements taken for this report will serve as a baseline for future measurements. Sediment Sampling One grab sample of stream bed sediment was collected adjacent to each sediment pin location. The sample was collected after sufficient time has past since the last storm event (base flow conditions). The purpose of this was to collect a sample more representative of deposition conditions. A garden-type shovel was used to collect the top 4 inches of sediment in the stream bottom. The sample was then placed into a 1-gallon size ziplock bag, with at least enough to fill the bag half way. Each bag was labeled with the time, date, and sample location. A duplicate sample at one location should have been taken. This will be done at a later date, as discussed in Section

26 The sediment samples were then brought to the MTU Civil Engineering soils lab, and tested using a sieve analysis. No hydrometer testing was completed (no characterization of fines below the 200 sieve). The sieve sizes that were used are indicated below, and generally correspond with ASTM soil size classifications. The classification is based on the particle passing through the corresponding sieve size. Table 5.1: Sieve sizes. Sieve No. Opening ASTM mm Classification 3/4 inch 19.0 Fine Gravel 3/8 inch Coarse Sand Medium Sand Fine Sand Fines (Silt and Clay) The sample preparation and sieving procedures were completed in general accordance with methods identified in ASTM D DATA COLLECTION Sediment pin installation and sediment sampling was completed at the locations shown on Figure 1.3, and as indicated in Table 1.2. Sediment sampling was completed at the same locations that sediment pins were installed, unless otherwise indicated in Table 1.2. Sieve analyses were done for the locations indicated in Table 1.2, unless otherwise indicated. 5.4 RESULTS AND ANALYSIS The following table represents the sediment pin locations and their measurements: Table 5.2: Sediment pin measurements. Location Measurement (ft) Only a sieve analysis was done at Location 2-1. This is because this location seemed to represent the most natural sediment conditions of the stream. However, at the sampling time, it was noticed that the sediment sizes were too large to put through a sieve. Instead, appropriately-sized sediments were collected from a small sediment pool on the west side of the point location. These sediments do not necessarily represent natural sediment conditions of the stream. 25

27 Results from the sieve analysis are plotted below: Figure 5.1: Grain size distribution for Huron Creek. Using Figure 5.1 and the Unified Soil Classification flow chart, it was concluded that all four points that were tested consisted of poorly graded sand (SP) (Coduto, pg 148). From the sieve analysis, since most of the particles for all four curves fall between the 0.25 and 2 mm, the sand is mostly fine sand. 26

28 6.0 OTHER EROSION MONITORING 6.1 INTRODUCTION The purpose of this portion of the geomorphology study was to document any areas of erosion within the creek channel or riparian areas that were not addressed by the Bank Erosion Hazard Index (BEHI). Areas addressed by the BEHI are either representative reaches of the creek or reaches where bank erosion is significant. This portion of the overall study addresses erosion areas that have the potential to be a source of sedimentation, and those areas that were not suitable for evaluation by the BEHI (such as concrete-lined banks that are undercut). 6.2 PROCEDURE Materials required for Other Erosion Monitoring : 1. Field notebook, pencil 2. Camera 3. GPS tape A 200-foot buffer zone along both sides of Huron Creek was field inspected for areas of erosion that were not addressed under the BEHI portion of the study. Field surveyors walked the length of the creek and through/along the buffer zone documenting areas of soil erosion and/or deposition. A photo was taken of these areas and their approximate location (GPS coordinates) was documented in a field notebook. 6.3 DATA COLLECTION Monitoring that falls under Other Erosion Monitoring was completed within the 200 ft buffer zone shown on Figure 6.1 and as indicated in Table

29 Figure 6.1: Other erosion monitoring locations. 6.4 RESULTS AND ANLYSIS Pictures of each location can be found in Appendix E. Also, see section 8.4 for more details on how these locations should be monitored. 28

30 7.0 PHOTOGRAPHS 7.1 REACH 1 Figure 7.1 is a picture taken looking upstream towards Location 1-2 Figure 7.1: Location REACH 2 Figure 7.2 is a picture taken looking upstream towards Location 2-1. Figure 7.2: Location

31 Figure 7.3 is a close up picture taken of the sedimentation occurring at Location 2-4. Figure 7.3: Location REACH 3 Figure 7.4 is a picture taken looking upstream from Location 3-3. Figure 7.4: Location

32 7.4 REACH 4 Figure 7.5 is a picture taken looking downstream towards Location 4-3. Figure 7.5: Location REACH 5 Figure 7.6 is a picture taken looking at Location 5-2. Figure 7.6: Location

33 8.0 RECOMMENDATIONS Taking into account the baseline measurements, surveys, and other observations, the following sections provide possible solutions to some of the problems that have been identified thus far. 8.1 GEOMORPHOLOGY COMPLETION Table 8.1, below, shows the surveys that are left to be completed following the same procedures outlined previously in this document. Table 8.1: Geomorphology completion surveys. Location Survey Type(s) 1-2 X-SECTION & SLOPE X-SECTION & SLOPE 6-1 PHOTO 6-2 PHOTO & LONGITUDINAL PROFILE* 6-3 PHOTO 7-1 PHOTO The incomplete surveys listed in Table 8.1 should not have an impact on the recommendations listed below. The completion of these surveys will be to provide a more complete baseline for Huron Creek that can be used in later evaluations. *See Section below for more details on the longitudinal profile survey. 8.2 REACH 6 RECOMMENDATIONS Reach 6 is the most heavily impacted Reach by development along Huron Creek. The developmental impact is caused by the Copper Country Mall and the development surrounding and including Festival Foods. Due to the impermeable surfaces in these areas, high flows enter Reach 6 in storm conditions. The impermeable surfaces causes the lag time of the storm to be dramatically shorter than natural conditions, causing a flash flood effect in Reach 6. This leads to high rates of erosion. This impact may have a direct effect on the detention ponds located behind Wal-mart. As erosion occurs on Reach 6, sediment is likely being washed into these detention ponds. If this is allowed to continue, the detention ponds will be less effective and will need to be dredged more frequently than originally designed. Also, the impacts will eventually affect the Copper Country Mall as the head cut at Location 6-2 (see Figure 1.3) works its way upstream towards the mall parking lot. There has been noticeable movement in the head cut already. This problem has a longer estimated time to be solved, as it is a slow moving process. Hopefully it will be solved by the implementation of the recommended detention pond helping to control the high flow rates that are currently an issue. 32

34 At Location 6-3 (see Figure 1.3), there is significant erosion occurring due to the high flow rates. The erosion of the banks at this location has caused the ground above the bank to fall into the creek, causing large amounts of sediment to flow into Reach DETENTION POND The most important recommendation is the addition of a detention pond to manage the high flows caused by the developed areas of the Copper Country Mall and the Festival Foods area. The proposed location can be found in Figure 8.1. This location was chosen to eliminate as little of the developed area as possible and is not a mandatory location. Figure 8.1: Proposed detention pond location. There are many possibilities for detention pond designs that would be acceptable. This is one possible design, with assumptions that can be found in Appendix F. The detention pond was designed with the aid of HydroCAD. The design is a prismatoid with bottom dimensions of 200 ft by 250 ft. It has slopes of 2 ft/ft. A 12 inch diameter, 25 ft long corrugated metal pipe (CMP) culvert will be used to move water from the detention pond to the creek. 33

35 The goal of the detention pond is to return the flows entering Reach 6 as closely as possible to natural conditions that existed prior to development LOCATION 6-3 BANK STABILIZATION At Location 6-3, bank stabilization is recommended. Since there has already been significant damage, there are not many possibilities for improvement. Joe Rathbun with the MDEQ made a couple of recommendations, including placing rocks at the toe of the bank and revegetating the eroding slope. Placing rocks at the toe would require knowledge of the flow in order to determine the appropriate rock sizes. To revegetate the eroding slope, it would be important to research plants that are native to the area and the appropriate root depths to avoid continued erosion. The addition of the detention pond would slow the current erosion rate; however, the current condition of the slope would not improve without implementing one or both of these recommendations or another engineered solution. 8.3 WATERFRONT PARK The most important improvement needed at the Waterfront Park is to stabilize the banks. This can be done in a variety of ways. The most feasible possibilities include revegetation, inserting gabions, and making the slopes shallower. In order to properly revegetate the park, it is important to research which plants are native to the area and would help prevent erosion. Gabions would provide stabilization of the toe, making a semi-permanent structure that is more aesthetically pleasing than other options. Finally, making the slopes shallower would not only improve the erosion problem at the park, but would make the water more accessible for recreation. There is currently a more detailed recommendation for the Waterfront Park that is under consideration by the City of Houghton which can be found in Appendix G (Dr. Alex Mayer). 8.4 CONTINUED MONITORING Table 8.2 shows the recommended frequency of surveying different locations along Huron Creek for continued monitoring. These are recommended based on the estimated availability of volunteers, difficulty of the survey, and the current conditions. If any of these criteria should significantly change, then Section 8.2 should be reevaluated. 34

36 Location Name Table 8.2: Continued Monitoring Frequency Recommendations Frequency (yrs) Survey Type(s) 1-2 BEHI 5 HABITAT 5 X-SECTION & SLOPE 10 SEDIMENT 2 1-a MONITOR STONE WALL b MONITOR COLLAPSED STONE WALL c MONITOR CULVERT AREA EROSION SEDIMENT (SIEVE ONLY) 5 2-a MONITOR CONCRETE BANK EROSION BEHI 5 HABITAT 5 X-SECTION & SLOPE 10 SEDIMENT b MONITOR CULVERT AREA EROSION 5 3-a MONITOR CULVERT AREA EROSION BEHI 5 HABITAT 5 X-SECTION & SLOPE 10 SEDIMENT b MONITOR PARKING LOT RUNOFF EROSION 5 4-a MONITOR CULVERT AREA EROSION 5 4-b MONITOR PARKING LOT RUNOFF EROSION BEHI 5 HABITAT 5 X-SECTION & SLOPE 10 SEDIMENT c MONITOR ORV ROAD EROSION d MONITOR RAZORBACK DEVELOPMENT HILL EROSION BEHI 5 HABITAT 5 X-SECTION & SLOPE 10 SEDIMENT BEHI 5 HABITAT 5 X-SECTION & SLOPE 10 SEDIMENT BEHI 5 HABITAT 5 X-SECTION & SLOPE 10 SEDIMENT BEHI 5 HABITAT 5 X-SECTION & SLOPE 10 SEDIMENT BEHI 5 HABITAT 5 X-SECTION & SLOPE 10 SEDIMENT

37 8.4.1 HEAD CUT MONITORING To reduce the future impact on the Copper Country Mall parking lot that could be caused by the head cut at Location 6-2, it is recommended that the head cut be monitored. One possible way to monitor this location, recommended by Joe Rathbun from MDEQ, is to perform a longitudinal profile. This should be performed as a baseline and used for future monitoring of the head cut. To complete the longitudinal profile, elevations must be taken first, starting and finishing at known GPS coordinates for reference. A surveyor s tape is laid out along the stream and points will be taken at 5 ft intervals. Points should also be taken where there is significant change in the longitudinal profile. A surveyor s level is used to measure the relative elevations at each interval. The profile should be completed for a distance approximately 100 ft upstream and downstream of the head cut. The field data can be plotted using the Mecklenburg Spreadsheet. 36

38 9.0 REFERENCES Annis Water Resources Institute - GVSU. Quality Assurance Project Plan for the White River Watershed Planning Project C. Harrelson, C. Rawlins & J. Potyondy. Stream Channel Reference Sites: An Illustrated Guide to Field Technique. United States Department of Agriculture, Forest Service Rocky Mountain Research Station. General Technical Report RM D.P. Coduto. Geotechnical Engineering: Principles and Practices. Prentice-Hall. New Jersey Dr. Alex Mayer Director, Michigan Tech Center for Water & Society Department of Geological & Mining Engineering & Sciences Michigan Technological University 1400 Townsend Drive Houghton, MI Phone: , Fax: , asmayer@mtu.edu Houghton Keweenaw Conservation District. Quality Assurance Project Plan for the Eagle River Watershed Management Plan Huron Creek Watershed Vision Statement Joe Rathbun. Water Bureau Nonpoint Source Monitoring Coordinator. Michigan Department of Environmental Quality (MDEQ). Personal Communication. July- September Linda Kersten - Graduate Candidate, Environmental Engineering Department of Civil and Environmental Engineering Michigan Technological University 1400 Townsend Drive Houghton, MI Phone: , Fax: , ldkerste@mtu.edu Michigan Department of Environmental Quality. Quality Assurance Project Plan (QAPP) Guidance for Water Quality Monitoring. Modified BEHI Standard Operating Procedure (SOP) written by Joe Rathbun Michigan Department of Environmental Quality - Water Bureau Nonpoint Source Unit Contact Information: (517) , rathbunj@michigan.gov U.S. Forest Service Stream Reach Inventory and Channel Stability Evaluation,

39 APPENDIX A BEHI FORMS & FIELD DATA The field data for the BEHI can be found in the following document: BEHI Field Notes 38

40 APPENDIX B STREAM HABITAT FORMS & FIELD DATA The field forms for the stream habitat survey are found in the following document: Stream Habitat Field Notes 39

41 APPENDIX C CROSS SECTION & SLOPE FIELD DATA The cross section and slope field data can be found in the following document: Cross Section and Slope The slope calculations and sieve analysis can be found in the following document: Sieve Analysis and Slope Calculations 40

42 APPENDIX D MECKLENBURG SPREADSHEET The Mecklenburg Spreadsheet can be found in the following document: Mecklenburg Spreadsheet 41

43 APPENDIX E OTHER EROSION MONITORING PICTURES The following table is an index for the pictures used for Other Erosion Monitoring Location Description Picture 1 a Undercut stone wall 1 a 1 b Collapsed stone wall on east bank 1 b 1 c Culvert erosion 1 c 2 a Concrete bank erosion 2 a 2 b Culvert erosion (east side) 2 b 3 a Culvert erosion and possible runoff 3 a 3 b Parking lot runoff and erosion 3 b 4 a Culvert erosion 4 a 4 b Runoff from parking lot 4 b 4 c Stone road erosion 4 c 4 d Hill erosion (east side buffer zone) 4 d 42

44 APPENDIX F HYDROCAD STORM POND SIZING NOTES/ASSUMPTIONS Assumptions made for the detention pond design can be found in the following document: HydroCAD Assumptions The HydroCAD files are below: Pre-development Post-development Detention Pond 43

45 APPENDIX G WATERFRONT PARK PLANS The current plans for the Waterfront Park (under consideration) are in the following document: Waterfront Park Plans 44