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HomeMy WebLinkAbout07-24-09 Council Handouts FIL E COP Y Pte City of Oak Park Heights 14168 Oak Park Blvd. N • Box 2007. Oak Park Heights, MN 55082 • Phone (651) 439 -4439 • Fax (651) 439 -0574 July 24th, 2009 MEMO TO: City Council Members FROM: Eric Johnson, City Administrator RE: Joint Meeting w/ BCWD I have enclosed the information provided by the BCWD for our joint meeting on Tuesday, July 28th at 6pm. For what it is worth, I have asked Karen Kill the BCWD administrator if the intention of the meeting was to seek financial assistance from the City. She did not believe that was the intention of the meeting rather to discuss the functioning of the pond and some possible retrofits. Karen Erickson from Bonestroo will also be in attendance to assist in possible technical question from the City's perspective. During the design /construction phase of this project, there was some difference in opinion at the time between Bonestroo and FOR (the BCWD engineering firm) as to the long -term functioning of the pond to "infiltrate" as opposed to total water storage capability. As I best recall, the pond was constructed to allow for infiltration, but was also sized to accommodate non - infiltration. w B. [� 1380 W FRONTAGE RD S H 1 G H. w A. Y 3 6 S TILLWATER, MN C P**,,- E E K 5 5 0 8 2 WATERSHED .2 x26 IPHoN 651.275.1254 1 FAX I DISTRICT www.BCwD.0RG AGENDA SPECIAL MEETING OF THE BOARD OF MANAGERS Tuesday, July 28` 2009 6:00 -7:00 PM Joint Board Workshop with Oak Park Heights Council Oak Park Heights City Hall Council Chambers 14168 Oak Park Blvd N, Oak Park Heights 1. Call to order @ 6:00 P.M. 2. Approve Agenda 3. Kern Center Pond (6:00 -6:35) - Presentation by Lisa Tilman, FOR o Results of BCWD Monitoring 2005 -07 and Soils Investigation 2008 o Possible Subwatershed Retrofits by BCWD 4. Brown's Creek Biota TMDL Study (6:35 -6:55) — Presentation by Andrea Plevan, FOR • Identified Stressors — Total Suspended Solids, Temperature, Dissolved Oxygen and Copper • Waste Load Allocations and Load Allocations 5. Other Opportunities for Collaboration 6. Adjourn 7:00 PM MANAGERS: CRAIG LEISER. PRESIDENT - RICK VANZWOL, VICE- PRESIDENT - GAIL PUNDSACK VICE - PRESIDENT CONNIE TAILLON, TREASURER - GERALD JOHNSON, SECRETARY Brown's Creek Watershed District 2007 Best Management Practice (BMP) Monitoring Report A. Project Background In 2005, the Brown's Creek Watershed District (BCWD) levied tax funds for the monitoring of Best Management Practices (BMPs). The BMP Monitoring Program was initiated to evaluate the performance of alternative stormwater management practices given the District's standards for water quality and volume control. Since the District's Rule Revision process, which resulted in the adoption of amended Rules in May of 2007, the BCWD may also use the BMP Monitoring Program to evaluate the performance of pretreatment facilities as well as thermal contributions of stormwater management facilities to groundwater dependent natural resources. Data collected via the BMP Monitoring Program can be used by the District and local units of government (LGUs) to establish or modify future performance standards as well as maintenance requirements or it may be used in the design and construction of future stormwater management facilities. In 2005, the BMP Monitoring Program evaluated the performance of two infiltration facilities: the Kern Center Pond and an infiltration basin on the Bradshaw development site. The 2006 and 2007 BMP Monitoring Programs continued the evaluation of these two infiltration facilities. The 2005 BMP Monitoring Report describes the Kern Center Pond and the infiltration basin on the Bradshaw development site in detail. The following bullets summarize the main characteristics of these facilities as presented in the 2005 BMP Monitoring Report: Kern Center Pond • Regional stormwater management facility designed to serve the Kern Center Commercial Area which is approximately 92 acres in size. • Construction of the Kern Center Pond modifications began in December of 2004 and final excavation and restoration of the site was completed in the spring of 2005. • The pond outlet consists of a 48" x 18" skimmer opening at the bottom of a 72" diameter manhole. The outlet pipe on the back of the manhole is a 42" reinforced concrete pipe (RCP) that has been restricted with a 12" PVC section in order to reduce peak discharge rates. A high water level outlet grate is located at the top of the manhole structure. • Local soil borings indicate the site is dominated by fine to medium grained silty sands separated by silts and less frequently by clay. Site observations during construction noted water moving laterally along bedding planes from west to east. Brown's Creek Watershed District Pate ] Emmons & Olivier Resources, Inc. BMP Monitoring Program High angle cross beds with fractures perpendicular to bedding planes were also noted on site. Such fractures provide conduits for vertical movement of water making the site conducive to infiltration. ■ The BCWD and the City of Oak Park Heights developed a Cooperative Agreement for the Kern Center Pond. Per this agreement, the BCWD is responsible for on -going monitoring of the Pond and the City will be responsible for the maintenance requirements. Bradshaw Infiltration Basin • Infiltration basin located on a four -lot commercial development that is 26 acres in size. • Approximately 21 percent of the site drains to the infiltration basin. The contributing drainage area consists of direct runoff from three of the four commercial lots. • At this point in time, one of the four commercial lots (one of the lots in the contributing drainage area) is undeveloped. Because the contributing drainage area hasn't been completely developed and stabilized, the infiltration basin is acting as a temporary erosion and sediment control facility. There is a layer of filter fabric in the bottom of the basin to protect the underlying permeable soils from clogging. As a result, the infiltration rates measured in this facility are most likely due to infiltration occurring on the sides of the facility. • In 2005, there were multiple instances of driving in this infiltration basin including truck, four - wheeler and snowmobile traffic. This activity appears to have ceased since that time. • The basin's outlet is an overland emergency overflow at an elevation of 943.5 feet. The basin did not outlet during the 2005 - 2007 monitoring seasons. This report evaluates the data collected in 2007 and is intended to serve as an addendum to the initial 2005 report. A vegetation survey and assessment was conducted on June 24, 2007 by Pat Conrad, Emmons & Olivier Resources, Inc. and is described in detail in the 2006 BMP Monitoring Report. B. Methodology As mentioned in the previous section, the 2007 BMP Monitoring Report presents infiltration data collected in 2007. Infiltration Rate Analysis At this point in time, the BCWD's BMP Monitoring Program evaluates the performance of infiltration practices by monitoring infiltration rates. In order to monitor infiltration rates, water level monitoring equipment was installed at each site. This equipment was obtained, installed, and monitored by the Washington Conservation District. The equipment and monitoring methods remained the same as in 2005 except that field inspection and maintenance of each of the data loggers was performed routinely every 2 Brown's Creek Watershed District Page 2 Emmons & Olivier Resources, Inc. BMP Monitoring Program weeks at a minimum instead of every 8 days on average. The monitoring equipment was installed in the Kern Center Pond on April 20, 2007 and was removed on October 30, 2007. In the Bradshaw Infiltration Basin, the monitoring equipment was installed April 20, 2007 and removed October 23, 2007. Photographs of the Kern Center Pond were taken when staff visited the site to take manual water level readings. The photographs taken from a consistent vantage point are included as Appendix A. Local precipitation data were collected from the WCD Station in the Stillwater area. This precipitation data is presented with the water levels in the two infiltration basins. After collecting the 2007 monitoring data, the WCD calibrated the data set by evaluating the difference in the raw data from the measured staff gauge readings. If significant data logger drift or unexplained errors were noted, the data was shifted to account for the average difference between the staff gage readings and the raw data. In 2007, no alterations to the data were necessary to correct for logger drift or other errors. Emmons & Olivier Resources, Inc. (EOR) performed the infiltration rate analysis using the data collected and calibrated by the Washington Conservation District. While the method for calculating infiltration rates was described in the 2006 BMP Monitoring Report, it will be described again in this report. Infiltration rates are determined by calculating the slope (A depth /A time) of the water elevation /depth vs. time curve, every four hours, for each drawdown event, averaged over 0.25 foot intervals. In the Kern Center Pond, where the infiltration rates are lower, these values are calculated over eight hour intervals. If the sign of the infiltration rate indicated that the water elevation had increased during a four -hour time period, that rate was not used in the average for that depth interval. Drawdown events were determined from a visual inspection of the water elevation /depth vs. time curve; a drawdown was considered a separate event if there were no substantial changes in infiltration rate (slope) within the event. Volumetric infiltration rates were computed by multiplying the infiltration rates by the average area of the basin for the same elevation interval that was used in averaging the infiltration rates. C. Results C -1. Kern Center Pond Infiltration Rate Analysis Figure 1 is a graphical representation of the calibrated data after it was collected in the field: it illustrates the water surface elevation in the Kern Center Pond over the 2007 monitoring period (April 20 to October 30). As Figure 1 illustrates, ten infiltration events were evaluated over the course of the 2007 monitoring season for the Kern Center Pond. The size of the rainfall event, the range and average of the infiltration rates and the range and average of the volumetric infiltration rates are presented in Table 1. In 2007, the maximum infiltration rate was 0.10 in /hr and the minimum was 0.00 in /hr. Similarly, the maximum volumetric infiltration rate was Brown's Creek Watershed District Page 3 Emmons & Olivier Resources, Inc. BMP Monitoring Program 0.56 cfs and the minimum was 0.00 cfs. Note that the outlet was operational for 2007 and that all average infiltration rates were determined for elevations below 928.6 feet (elevation of the orifice). The pond retained runoff and eliminated downstream flow throughout the spring and much of the summer with outflow only occurring after the relatively larger rainfall events in August. Figure 1: Water Surface Elevations in the Kern Center Pond • Water Surface Elevations OEvent Start ❑ Precipitation 931 - -- 3 Outlet Elevation 928.6 930.5 ° 930 - -- 2.5 c 929.5 -- -- -- - 0 2 ' 929 -- - - - c m : -. w 928.5 - - - - _ - - - - - - - o CD ' ❑ ❑ 1.5 a M 928 ^ a v 7 927.5 - -- - - - -- -- °' 927 -- - ° -- - - - - -- ❑ 1 a` 926.5 - -- ° n 0.5 ❑ �t 926 e ❑ n - -- - ° -- ❑ 11 0 ° ° ❑ ❑ ❑ ❑ IM 925.5 ° ° r m Ca�mrmRm ° ;,,, mm� 0 21- Apr -07 20- May -07 18- Jun -07 17- Jul -07 15- Aug -07 13- Sep -07 12- Oct -07 Time [day- month -year] Table 1: Infiltration Rate Summa ry for Kern Center Pond Event Average Infiltration Rate Infiltration Rate Range Volumetric Volumetric Start Date Rainfall Duration Infiltration Rate Infiltration Rate Infiltration Rate Infiltration Rate Event (date) (in.) (hr) (ft/day) (in /hr) (cfs) (in/hr) (cfs) min max min max 1 4/24/2007 0.27 137 0.05 0.03 0.09 0.00 0.06 0.00 0.20 2 4/30/2007 0.31 186 0.04 0.02 0.08 0.00 0.10 0.00 - 0.36 3 5/9/2007 0.20 324 0.05 0.02 0.20 0.00 0.06 0.00 0.56 4 5/24/2007 0.88 119 0.05 0.02 0.08 0.00 0.04 0.00 0.15 5 5/31/2007 0.58 371 0.05 0.03 0.11 0.00 0.05 0.00 0.42 6 6/18/2007 0.21 357 0.05 0.02 0.19 0.00 0.06 0.00 0.56 7 7/3/2007 0.31 118 0.05 0.03 0.24 0.00 0.06 0.00 0.56 8 7/8/2007 0.15 125 0.06 0.03 0.26 0.00 0.06 0.00 0.56 9 7/14/2007 0.28 300 0.05 0.03 0.09 0.00 - 0.06 0.00 0.32 10 1 7/26/2007 0.61 367 0.05 0.03 0.07 0.00 0.05 0.00 0.13 Another way to analyze the data set is to compare the infiltration rates from each event with respect to surface water elevation (see Figure 2). Figure 2 displays an average of the infiltration rates measured for each 0.25 ft increase in water surface elevation. Typically, Brown's Creek Watershed District Page - 4 Emmons & Olivier Resources, Inc. BMP Monitoring Program the infiltration rate decreases as the water surface elevation decreases because the higher pressure of the water (head) moves the water into the soils faster, because there is more area of contact between the water and the soils, and because soils on the sides of the basin are less likely to be impacted by sedimentation of soils washed into the basin. In the 2007 case, the infiltration rate did not change as the water surface elevation decreased over the 2.5 foot range of observed water surface elevations below the outlet. The 2007 observed infiltration rates are generally consistent with those observed in 2006. In 2005 the basin was operating at higher elevations because the outlet was intentionally blocked to allow vegetation establishment and higher average infiltration rates were observed. Figure 2: Summary of Infiltration Rates for the Kern Center Pond 0.12 x-2007 t 2006 - x-2005 0.10 V i 0.08 - c m Y W 0.06 1 c o CU = 0.04 — c 0.02 - - - - 0.00 - 926.0 927.0 928.0 929.0 930.0 931.0 932.0 Water Surface Elevation [ft] The long duration of infiltration events in this basin means that evaporation is another process that could be removing water from the basin. The measured evaporation rate (in St. Paul) averaged about 0.007 in /hr throughout the monitoring season with a monthly average ranging from 0.006 in /hr in October to 0.012 in /hr in June and July. Therefore, evaporation contributes to a portion, but not all, of the measured infiltration rate. Transpiration by the vegetation in the basin also contributes to the measured infiltration rate. The photograph log indicates dense vegetation present at the boundaries of the basin throughout the monitoring season. In fact, the 2007 data shows a diurnal pattern of decreasing water level during the day and more constant water level at night. This pattern was not observed in past years, and could either be indicative of the strong influence of evapotranspiration on the loss of water from the basin or could simply be the Brown's Creek Watershed District Page 5 Emmons & Olivier Resources, Inc. BMP Monitoring Program sensitivity of the equipment to temperature fluctuations.. As a result, in the Kern Center Pond, the measured infiltration rate appears to be a combination of infiltration and evapotranspiration with evapotranspiration playing a larger role than previously thought. C -2. Bradshaw Infiltration Basin Figure 3 is. a graphical representation. of the water surface elevation data as it is collected in the field: it illustrates the water surface elevation in the Bradshaw Infiltration Basin over the 2007 monitoring period (March 20 to October 23). Eighteen infiltration events were identified over the course of the 2007 monitoring season. The size of the rainfall event, the range and average of the infiltration rates and the range and average of the volumetric infiltration rates are presented in Table 2. In 2007, the maximum infiltration rate was 0.84 in/hr and the minimum was 0.00 in/hr. The maximum volumetric infiltration rate was 0.39 cfs and the minimum was 0.00 cfs. Figure 3: Water Surface Elevations in the Bradshaw Infiltration Basin • Water Surface Elevations OEvent Start ❑ Precipitation 3 941.38 Overflow Elevation 943.5 - -- i 941.18 2.5 V c 940.98 2 c j 940.78 -. d � m 940.58 0 � ❑ ❑ 1.5 c 't 940.38 Jr11 I CL d 940.18 1 a. r R 939.98 -- - 0.5 939.78 ❑ 939.58 +— ❑ - -- 0 7- Apr -07 6- May -07 4- Jun -07 3- Jul -07 1- Aug -07 30 -Aug- 28 -Sep- 27 -Oct- 25 -Nov- 07 07 07 07 Time [day- month -year] Brown's Creek Watershed District Page 6 Emmons & Olivier Resources, Inc. BMP Monitoring Program t Table 2: Summary of Infiltration Rates for the Bradshaw Infiltration Basin Event Average Infiltration Rate Infiltration Rate Range Volu metric Volumetric Start Date Rainfall Duration Infiltration Rate Infiltration Rate Infiltration Rate Infiltration Rate Event (date) (in.) (hr) (ft/day) (in/hr) (cfs) (in /hr) (Cfs) min max min max 1 4/3012007 0.31 18 0.27 0.13 0.006 0.06 0.18 0.00 0.01 2 5/5/2007 n 8 0.30 0.15 0.007 0.12 0.18 0.01 0.01 3 5/7/2007 0.30 11 0.12 0.06 0.003 0.06 0.06 0.00 0.00 4 5/9/2007 0.20 37 0.11 0.05 0.002 0.03 0.12 0.00 0.01 5 -a 5/23/2007 0.60 16 0.54 0.27 0.047 0.21 - 0.33 0.03 0.06 5-b 5/24/2007 0.88 81 0.21 0.10 0.010 0.00 0.18 0.00 0.03 6 6/18/2007 0.21 36 0.28 0.14 0.006 0.06 0.30 0.00 0.01 7 8/14/2007 2.73 70 0.68 0.34 0.081 0.03 0.84 0.00 0.39 8 8/28/2007 0.76 69 0.29 0.14 0.017 0.00 0.33 0.00 0.06 9 9/18/2007 0.29 45 0.34 0.17 0.020 0.06 0.27 0.00 0.05 10 9/20/2007 1.75 92 0.35 0.18 0.026 0.03 0.48 0.00 0.09 11 9/24/2007 0.31 47 0.12 0.06 0.003 0.03 0.09 0.00 0.00 12 9/26/2007 0.21 54 0.13 0.06 0.003 0.03 0.12 0.00 0.01 13 9/30/2007 1.43 43 0.35 0.17 0.022 0.06 0.30 0.00 0.06 14 10/2/2007 0.91 53 0.28 0.14 0.016 0.03 0.21 0.00 0.04 15 10/5/2007 0.27 57 0.22 0.11 0.010 0.03 0.18 0.00 0.03 16 10/8/2007 1.38 84 0.20 0.10 0.010 0.03 0.24 0.00 0.05 17 10/19/2007 0.71 92 0.17 0.08 0.008 0.03 0.18 0.00 0.03 Another way to analyze the data set is to compare the infiltration rates from each event with respect to surface water elevation (see Figure 4). Figure 4 displays an average of the infiltration rates measured for each 0.25 ft increase in water surface elevation. Thus, Figure 4 displays how the infiltration rate changes as water surface elevation changes. As would be expected, the rate of infiltration decreased as the water level in the basin decreased over the 2 foot range of observed water surface elevations. An increase in infiltration rates at higher water surface elevations was observed for 2006 and 2007. In 2007, the water surface elevation curves (Figure 4) show a change in slope (infiltration rate) when the water surface elevation is within about a half foot of the bottom of the basin. The difference in infiltration rates observed above and below this elevation for 2007 is summarized in Table 3. Infiltration rates within about a half foot of the bottom were lower than the rates at higher water surface elevations. Figure 4, however, indicates that the change in infiltration rate observed in the lower portion of the basin may simply reflect the general trend of decreasing infiltration rate as the water surface elevation decreases. Brown's Creek Watershed District Page 7 Ennions & Olivier Resources, Inc. BMP Monitoring Program Y Figure 4: Infiltration Rates for Bradshaw Infiltration Basin 0.90 - - -*-- 2007 0.80 X 2006 - f 2 00 5 0.70 L t 0.60 - -.. c u 0.50 IX o 0.40 -- w co 0.30 c 0.20 - - 0.10 0.00 - - - - -- - - - 939.5 940.0 940.5 941.0 941.5 942.0 Water Surface Elevation [ft] Table 3: Summary of Average Infiltration Rates for Bradshaw Infiltration Basin at Observed Elevation Break Average Infiltration Rate With Elevation Divide - 940 Infiltration Rate Infiltration Rate High erWa ter Elevatan Low Water Elevation Event ft/da in/hr (ft/day) - L hr 1 - 0.25 0.12 2 0.24 0.12 3 0.14 0.07 4 -- -- 0.12 0.06 5-a 0.49 0.24 -- -- 5-b 0.27 0.13 0.12 0.06 6 0.49 0.24 0.21 0.10 7 0.97 0.48 0.13 0.07 8 0.41 0.20 0.14 0.07 9 0.47 0.23 0.15 0.07 10 0.51 0.25 0.13 0.06 11 0.17 0.09 0.11 0.05 12 0.13 0.07 0.12 0.06 13 0.47 0.24 0.12 0.06 14 0.39 0.20 0.12 0.06 15 0.27 0.14 0.15 0.07 16 0.30 0.15 0.11 0.06 17 0.26 0.13 0.11 0.05 Brown's Creek Watershed District Page 8 Emmons & Olivier Resources, Inc. BMP Monitoring Program D. Conclusions D -1. Kern Center Pond Infiltration Rate Analysis As the results section indicates, the infiltration data collected for the Kern Center Pond for 2005 through 2007 evaluates the performance of the basin at two different sets of elevations, above the .outlet elevation in 2005 when the outlet was closed and below the outlet elevation in 2006 and 2007 (see Figure 2). This information is summarized in the following table (Table 4): Table 4: Kern Center Pond Infiltration Rate and Range Su mary, 2005 — 2007 Year Pond Elevation Average Rate Rate Range feet in /hr in /hr 2005 931.5 — 929.5 0.04 0.02-0.12 2006 928.5 — 926.0 0.02 0.00-0.06 2007 928.5 — 926.0 0.03 0.00-0.10 As mentioned previously, the pond was undergoing reconstruction in 2005. As a result, the outlet structure was not operational and the pond was allowed to bounce higher than it normally would given that the outlet elevation is 928.6 feet. The infiltration rates measured in 2006 and 2007 represent the infiltration capacity of the basin under normal operating conditions. To provide the storage needed to meet the volume control standard of the Rule, the design goal was to have the basin operate with an average water level of 926.6 feet. In 2006, the basin had an average water level of 927.7 feet, providing about half the needed storage volume. In 2007, the basin had an average water level of 928.2 feet, providing about 1 1 5 t the storage volume needed to meet the Rules. An overall infiltration rate of 0.25 inch per hour was assumed for the design of the Kern Center Pond. The infiltration rates used for the pond size analysis were determined using the following information: ■ A total of five soil borings performed along the perimeter of the pond in 2002; ■ The County Well Index developed by the Minnesota Geologic Survey; ■ The Soil Survey of Washington County; and ■ Field measured infiltration rates for Washington County (specifically for the SWWD and an infiltration basin constructed by the Minnesota Department of Transportation along State Highway 5 approximately two miles south of the Kern Center pond). The infiltration rates measured in 2006 and 2007 are lower than the design infiltration rates, however, it is difficult to draw specific conclusions from the two years of Brown's Creek Watershed District Page 9 Emmons & Olivier Resources, Inc. BMP Monitoring Program monitoring data regarding the. cause of the low infiltration rates. There are a number of reasons that the observed infiltration rates could be lower than the expected (design) infiltration rates including: Soil variability resulting in less permeable soils than anticipated by borings and surveys ■ Locally perched groundwater table ■ Smearing of the soils during construction ■ Clogging of the soils from biological activity in the portion of the basin with a constant standing water level or from sediment transported into the basin Having noted some of the reasons the basin may be under - performing at this point in time, it is difficult to make recommendations for remedial action without having a stronger basis from which to draw conclusions. It is encouraging to note that as the vegetation becomes more established, water loss rates increased slightly. However, additional investigation of the causes for the lower than expected infiltration rates is necessary to clarify the specific cause. D -2. Bradshaw Infiltration Basin As the results section indicates, the performance of the infiltration basin on the Bradshaw development site is consistent for 2005 through 2007 with increases in infiltration rate evident at higher water surface elevations. In general terms the pond seems to be operating fairly consistently (see Table 5). Table 5: Infiltration Rate and Rang Summary, 2005 — 2007 Year Pond Elevation Average Rate Rate Range feet in /hr in /hr 2005 942.0 — 939.5 0.30 0.15-0.54 2006 941.5 — 939.5 0.09 0.00-0.60 2007 941.4 — 939.5 0.14 0.00-0.84 As Figure 4 indicates, the infiltration rates in 2007 and 2006 above an elevation of 940.1 feet are higher than the rates measured at the same elevations in 2005. In fact, infiltration rates were higher in 2007 than in 2006 at elevations above about 940.4 feet. One of the reasons for this increase in rate may be that the pond was not subject to vehicular traffic in 2006 and 2007 as it was in 2005. The underlying soils (on the sides of the basin) may have "bounced" back after a season or two of freezing and thawing resulting in slightly higher infiltration rates. Additionally, the further establishment of vegetation may have increased the infiltration capacity of the soils by increasing its macro -pore structure. The assumed infiltration rate for the Bradshaw Pond was 2 inches per hour. This infiltration rate was taken from the best information available at the time of design, the infiltration rates given in the Washington County Soil Survey, and is not representative of the conditions expected in a constructed infiltration basin based on more recent data. For the soil conditions found on the Bradshaw development site, fine to medium grained sand Brown's Creek Watershed District Page 10 Emmons & Olivier Resources, Inc. BMP Monitoring Program and fine to medium grained silty sands, the expected long -term infiltration rate for a constructed infiltration basin is 0.6 inches/hour (source: Minnesota Stormwater Manual, 2005). As the results indicate, the basin operates at these rates at higher elevations. It is. important to note that this infiltration basin has not been finalized: until the last lot in the contributing drainage area is constructed and the site is stabilized, the basin will continue to operate with a filter fabric on the bottom protecting the underlying permeable soils from clogging. The pond did not outlet for any events occurring in 2007 (maximum rainfall event was 2.73 inches in 24 hours) and had a peak water surface elevation of greater than two feet below the outlet elevation indicating that the basin is operating as expected for the smaller, more frequent events. D -3. Recommendations The following are recommendations for the BCWD's BMP Monitoring Program: 1. Continue monitoring the Kern Center Pond to build a more comprehensive data set (of infiltration rates) and to fulfill obligations under the Kern Center Cooperative Agreement with the City of Oak Park Heights. 2. Consider conducting additional investigation at the Kern Center Pond in 2008 to more clearly identify the reason for the low observed infiltration rates and to identify potential solutions to increase infiltration capacity. Direct District engineers to develop scope of work to perform an infiltration capacity investigation. The plan may include soil borings, hand auger soils investigation, and groundwater level observation wells. 3. Direct monitoring service provider to continue taking pictures of each BMP in the same location at each site visit to create a photo log of the monitoring season (note that this is one of the requirements of the monitoring portion of the Cooperative Agreement with the City of Oak Park Heights for the Kern Center Pond). 4. Consider ceasing monitoring at the Bradshaw site for two years or until the basin is brought to final design and including an alternate site in the BMP monitoring program. The Bradshaw basin appears to be functioning as desired at this time. 5. Complete the Kern Center Pond vegetation inspection and maintenance activities recommended in 2006 to maintain or increase infiltration capacity and evapotranspiration potential: • Conduct minor weed control in the berm and fringe wetland planting areas, on the south end of the west side, and on the south side of the Kern Center Pond. • Monitor the Kern Center Pond berm and fringe areas for increased Purple loosestrife and Cattail populations to make sure they do not take over areas with native vegetation. Brown's Creek Watershed District Pa e 11 Emmons & Olivier Resources, Inc. BMP Monitoring Program o Re -seed the north end of the west side and the east side of the Kern Center Pond. The areas should be herbicided, tilled and reseeded. Care should be taken not to disturb the shrubs on the east side of the pond. • Plant additional native species along the south side of the Kern Center Pond to establish additional native species. • Plant the unvegetated areas approximately 2 inches into the water and 9 inches above the water level with the species identified on the original planting plan. Now that a normal water level of sorts has been established on the Kern Center Pond it is vital that this area be vegetated with the appropriate native plants. Browns Cree Watershed District Pape 12 Enimons & Olivier Resources, Inc. BMP Monitoring P a Appendix A: Kern Center Pond Photo Log 5 -30 -07 6 -12 -07 4 6 -29 -07 7 -17 -07 'z 7 .�._ IO N- 8-31-07 9 -11 -07 3 i- 10-12-0 7 fi Brown's Creek Watershed District Paae 13 Emmons & Olivier Resources, Inc. BMP Monitoring Program 651 Hale Avenue North Oakdale, Minnesota 55128 telephone: 651.770.8448 facsimile: 651.770.2552 www.eorinc.com Date July 6, 2009 To Karen Kill, Administrator Contact info BCWD cc Board of Managers Contact info BCWD From Lisa Tilman and Brad Aldrich Contact info FOR Regarding Kern Center Retrofit Investigation Background Under current climatological conditions the Kern Center Pond will provide regional rate control and water quality treatment, but will not completely provide the design level of volume control. As discussed in the Brown's Creek Watershed District 2007 Best Management Practice (BMP) Monitoring Report, to provide the storage needed to meet the volume control standard of the Rule, the design goal was to have the basin operate with an average water level of 926.6 feet. In 2006, the basin had an average water level of 927.7 feet, providing about half the needed storage volume. In 2007, the basin had an average water level of 928.2 feet, providing about 1 /5` the storage volume needed to meet the Rules. Precipitation during the monitoring period was somewhat lower than normal in 2006 and somewhat higher than normal in 2007. Based on 2006 and 2007 conditions, the Kern Center Pond is providing infiltration capacity for the runoff from the entire site from a rainfall event of about 1.1 inches. Approximately 9.3 acre feet of additional storage /infiltration would be needed to meet the volume control requirements for the Kern Center Area. At the June Board Meeting a scope of work was approved to further investigate small scale infiltration and volume control projects in the Kern Center Pond drainage area in order to provide the level of volume control required for the area under the 2000 Rules. Site Visit FOR staff visited sites in the Kern Center Area on June 17, 2009. FOR walked the developed portions of the site focusing on areas of existing open space or areas with the potential for relatively simple modifications to enhance volume control. Potential Areas for Volume Control Retrofit Projects The roadside ditches were identified as the most feasible location for volume control enhancement for the currently developed portions of the Kern Center area. The developed properties have been designed to drain to the roadside ditch, or directly to the Kern Center Pond for those properties adjacent to the pond, with no aboveground treatment potential onsite. The open roadside ditch then transports drainage to the Kern Center Pond. The exception is the DDD, LLC property which has much of its drainage going to a small onsite pond that had a water level well below the apparent outlet elevation at the time of the site visit. The roadside ditch is currently primarily vegetated with mowed lawn grass although some areas of cattails are present in front two of the WATE Enterprises properties. The Post Office property is vegetated with native plants, including in the ditch. Enhancing volume control in the ditches could focus on increasing temporary storage with ditch checks and increasing infiltration into the soil or increasing evapotranspiration through vegetation. For most An Equal Opportunity Affirmative Action Employer Emmons & Olivier Resources, Inc. water I ecology I community memo 2of3 sites,. the potential storage is .confined to roadside ditches (see Potential Storage in tables below). However, on two properties: the Secure Mini Storage property and one of the WATE Enterprises sites, there is potential to expand the stormwater facility to include both the ditch and some adjacent land (see Alternate Storage in tables below). Additional volume control practices could also be incorporated into future development as it occurs. The estimated total potential volume control available in the ditches on currently developed properties in' the Kern Center area is about 8,150 cubic feet (0.19 acre feet) with a 6 inch check dam depth or about 20,000 cubic feet (0.46 acre -feet) with a one foot check dam depth. If the volume control features can be expanded into the alternate storage areas, the available volume control increases to 32,270 cubic feet (0.74 acre feet) with a 6 inch depth or 67,600 cubic feet (1.6 acre feet) with a one -foot depth. With check dams of about 6 inches in depth, the initial estimated otential storage is: Site (Property Owner) Approximate Event creating Approximate Event creating Potential Potential Storage. Alternate Storage Alternate Storage Storage Volume volume in direct Volume volume in direct contributing contributing drainage area drainage area Raduenz Dealership 3,855 cubic feet 0.53 inch none n/a Buberl 595 cubic feet 0.32 inch none n/a Secure Mini Stora a 1,235 cubic feet 0.41 inch 19,000 cubic feet 1.42 inch WATE Enterprises 484 cubic feet 0.50 inch none n/a WATE Enterprises 533 cubic feet 0.28 inch 6,888 cubic feet 0.61 inch DDD LLC 1,450 cubic feet 0.92 inch none n/a With check dams of about 1 foot in depth, the initial estimated p otential storage is: Site (Property Owner) Approximate Event creating Approximate Event creating Potential Potential Storage Alternate Storage Alternate Storage Storage Volume volume in Volume volume in direct contributing contributing drainage area drainage area Raduenz Dealership 9,488 cubic feet 0.78 inch none n/a Buberl 1,416 cubic feet 0.40 inch none n/a Secure Mini Storage 3,040 cubic feet 0.57 inch 38,000 cubic feet 2.24 inch WATE Enterprises 1,192 cubic feet 0.70 inch none n/a WATE Enterprises 1,312 cubic feet 0.36 inch 13,940 cubic feet 0.85 inch DDD LLC 3,568 cubic feet 1.58 inch none n/a Plantings recommended to enhance filtration, infiltration, and evapotranspiration include several native species as well as non - invasive cultivars and traditional landscape plantings. Planting designs could be naturalistic, similar to the existing Post Office landscape, or a more formal look with defined planting beds separated by turf grass that would aesthetically mirror the traditional landscapes of several current businesses. Typical vegetation that would be appropriate in either layout include: • Little Bluestein Schizachyrium scoparium • Red Osier Dogwood Cornus sericea • High Bush cranberry Viburnum trilobum • Black Chokeberry Aronia melanocarpa • Black -eyed Susan Rudbeckia fulgida Emmons & Olivier Resources, Inc. 651 Hale Ave N, Oakdale, MN 55128 p: 651.770.8448 f: 651.770.2552 www.eorinc.com memo 3of3 Soil investigations would be needed to indicate the estimated rate of infiltration in each ditch section, as well as any.confining layers, and depth to groundwater. Soil amendments could also be incorporated to increase soil storage of water for infiltration or evapotranspiration. Recommendation Incorporate additional volume control in the Kern Center area through enhancements to roadside ditches. Conduct soil investigations at each site prior to design and installation of volume control enhancements. Emmons & Olivier Resources, Inc. 651 Hale Ave N, Oakdale, MN 55128 p: 651.770.8448 f: 651.770.2552 www.eorinc.com S « Ak L Raduenz Dealefshiifl Raduenz Dealership 58th St N.� J y, Bube4 MiniStoragei ar'�'`�e.4;`:�tr,ai �a n4 Mini St rag -5 ` tx , T �• e e sue: a e. VtA4Ti _ z a a # Aw l a r' x .. - Y� A y } } a f'Y Y A 05 C t w V" . � f ` k I A 4 Kern ) Feet Potential—Storage—Areas �'� Center 0 125 250 500 Alternate_Sto rag e_Areas mat (T) 651.770.8448 / (F) 651.770.2552 www.eorinc.com Date I October 8, 2008 To I Karen Kill, District Administrator CC I BCWD Board of Managers From I John Barry, Toben LaFrancois, Lisa Tilman Regarding I Kern Center Pond Soils Investigation The Board approved the scope of work on August 11, 2008 to conduct an investigation of the potential for soil clogging in the Kern Center Pond. The scope for this project included collection of sediment cores from the Kern Center Pond and their analysis for soil composition and algae content. The goal of the project is to evaluate whether clogging of the soils in the bottom of the Kern Center Pond is causing the low infiltration rates observed in the pond. Investigation Methods FOR collected five sediment cores and five water samples on September 9, 2008. Cores were taken to the maximum depth possible, which ranged from 16 to 31 cm (6.3 to 12.2 inches) below pond bottom. Samples were taken from the pond bottom as this is the area most likely to exhibit soil clogging. The elevation of the pond bottom was surveyed at each of the sampling locations (Figure 1). In addition, the Kern Center Pond's water surface elevation and the water surface elevation of the wetland to the west/northwest were surveyed. Soil boring locations and elevations were recorded with a high resolution DGPS that was calibrated to a MnDOT control elevation. Cores were photo- documented and described and then separated for analysis of soil gradation and biological activity. Algae were sampled from the water column at the same five locations and taken from interstitial layers at the sediment -water interface of each core. Due to the consistency of materials encountered in this investigation, and their correspondence to materials encountered previously during pond reconstruction, it was decided that grain size distribution analysis of each sample was unnecessary. A grain size analysis was conducted for a homogenized sample of the entire 31 cm. core from Site 5 and the top 1 cm of the core from Site 2. The Site 5 analysis was chosen to represent the material of all samples due to the similarity of materials encountered at each site. The Site 2 analysis was conducted to investigate the possibility that the organic flocculent present in the top 1 cm of the pond bottom sediments was acting as a restrictive layer. In addition, organic content was analyzed for the top 1 cm of the Site 1 sample to characterize the make up of the surface sediment on the pond bottom. The algae samples from the water column and the surface sediments at the pond bottom were analyzed separately for each site for analysis of relative abundance of algae types. Since there was no significant difference in relative abundance of algae types between the water column samples and sediment samples, data are reported as a combined result for all samples. FOR is an Equal Opportunity Affirmative Action Employer Emmons & Olivier Resources, Inc. 651 Hale Avenue North Oakdale, Minnesota 55128 memo cont. (T) 651.770.8448 (F) 651.770.2552 www.eorinc.com Figure 1. Soil Core Locations and Pond Bottom Elevations in Kern Center Pond Z � Plel t 0°� IR 9 k Q I i I r oa' 1 9 0 0° SCALE IN FEET a ao ao •a. KERN CENTER POND Emmons & Olivier Resources, Inc. 651 Hale Avenue North Oakdale, Minnesota 55128 memo Cont. (T)651.770.8448 (F)651.770.2652 www.eorihc.com Results Visual inspection of cores after collection indicated the presence of an approximately 1 cm thick layer of organic flocculent in the top layers of each sample. This material consists of organic matter, likely dead algae of previous sesons, which have settled to the bottom. Colonial algae were noted in the top layers of all sites, and filamentous algae were noted in Sites 2 through 5. As seen in Figures 2 — 6, the soil type below pond bottom is generally consistent throughout the pond. The Munsell color of the soil is a classified as a 7.5 YR 4/4 Brown. This is similar to how these soils have been described in the past. The Munsell color description is often used in soil science as it provides a comparable color rather than a subjective description of the color of the sample. The soil classification based on the ASTM D422 grain size distribution testing is Silty Sand (SM). The lithological material found through this investigation is consistent with that noted in characterization work performed in 2002 and 2005. Results of the Grain Size Distribution Analysis illustrates that the material in both the surface and deeper portions of the Kern Center Pond are silty sands. The Site 5 sample, representing the deeper soils in the core, is approximately 74% sand, 24% silt, and 2% clay. The distribution of the Site 2 sample, representing the surface of the pond bottom material, is similar in composition but has a slightly larger proportion of fines (silt and clay). The organic material analysis found that 2.1% of the Site 1 sample is organic matter. The rest of the Site l sample was predominately silt. These grain size distributions indicate that the soils are likely not acting as a restrictive layer. In addition, the top several centimeters were noted to be bio- turbated by macro invertebrates in the pond. The boring and turning of the top layers by these creatures likely keeps this material porous. Hydraulic Conductivity for silty sands typically ranges from 10' cm /s to 10 " cm /s, rates that adequately remove water from systems. Figure 6 is the grain size distribution analysis conducted by Soil Engineering Testing. Table 1 shows relative abundance of the primary algae types found. There were no significant differences in species composition or size between sites. Dominant algae were colonial cyanobacteria of the genus Microcystis spp. (Figure 8) followed by Coelosphaerium spp. (Figure 9). These algae form mucilaginous sheaths around ovoid or shapeless colonies. The volume of the Microcystis sp. colonies did not exceed 0.724 cubic centimeters. Colonies easily broke apart with minimal agitation. Anabaena spp. (Figure 10) and Anabaenopsis spp. were also present. These filamentous cyanobacteria did not exceed 1.5mm in the samples taken, and easily break apart. Consequently, while the dominant algae in the Kern Center Pond form mucilaginous colonies or filaments, the small size and instability of the algae colonies makes it unlikely that they are responsible for soil clogging. Scientific literature does not report that these particular algae are responsible for clogging infiltration in other systems. In addition to surveying the soil boring locations, several surface water shots were collected to further elucidate the slow infiltration rates noted at the Kern Center Pond. The Kern Center Pond water surface was at an elevation of 928.15 ft on September 9, 2008 when field collection of soil cores was conducted. The water surface elevation at the open water wetland located roughly 1,120 feet to the west/northwest of the Kern Center Pond was 925.98 ft on that same date. The water surface elevation of this wetland may reflect the local groundwater elevation. This wetland water elevation is about 2 feet lower than the surface water elevation of the Kern Center Pond and about 4 feet higher than the pond bottom. This suggests that groundwater may intersect the Kern Center Pond. Additional analysis would be required to fully confirm this suggestion. Emmons & Olivier Resources, Inc. 651 Hale Avenue North Oakdale, Minnesota 55128 memo Cont. (T) 651.770.8448 (F)651.770.2552 www.eorinc.com Conclusion The material in both the surface and deeper portions of the Kern Center Pond sediments are silty sands with a gradation *suggesting that infiltration is possible at a greater rate than has been observed for the - pond. The dominant blue green algae were colonial and form mucilaginous sheaths, but are unlikely to be limiting infiltration due to their small size and fragile composition. Additionally, the algae present are not reported to clog infiltration in other systems. This analysis suggests that soil clogging is most likely not the reason for the lower than expected infiltration rate observed in the Kern Center Pond. Historically, the Kern Center Pond demonstrated significant infiltration capacity. The basin would fill with water, infiltrate, and often remain dry until the next rainfall event. Over time however, the basin's performance decreased and the basin was subject to longer periods of standing water on a routine basis. The cause for this decrease in performance was unknown. While additional investigation would be necessary to confirm that this is the case, it appears that a high groundwater table is the likely cause of this decrease in function. There are a number of potential explanations for this change in groundwater impact at the site. The pond reconstruction activities could have intersected a layer of perched groundwater . that is continuously contributing groundwater to the pond. Also, climate conditions could have resulted in increases in the local groundwater table. FOR can submit an updated scope of work to conduct a groundwater investigation for the Kern Center Pond if the Board would like to determine with more clarity if groundwater is indeed the key factor limiting infiltration in the pond. Under current climatological conditions, the Kern Center Pond will provide regional rate control and water quality treatment, but will not provide the design level of volume control. As discussed in the Brown's Creek Watershed District 2007 Best Management Practice (BMP) Monitoring Report, to provide the storage needed to meet the volume control standard of the Rule, the design goal was to have the basin operate with an average water level of 926.6 feet. In 2006, the basin had an average water level of 927.7 feet, providing about half the needed storage volume. In 2007, the basin had an average water level of 928.2 feet, providing about 1 /5` the storage volume needed to meet the Rules. Based on 2006 and 2007 conditions, an average of 9.3 acre feet of additional volume control storage would be needed to provide the design infiltration volume. To mitigate for the decrease in volume control provided, an option the BCWD could consider is to provide volume control in another part of the watershed downstream of the Kern Center Pond. One such option, the Century Power Ravine improvements, was investigated in the Highway 36 Water Quality Improvements Feasibility Study and Design Report. The Century Power Ravine includes the Kern Center Pond in its drainage area and was found to be feasible as a flood control project, but not as a volume control project due to the flow conditions at the site. The feasibility study did not identify other feasible volume control projects in this drainage area. Additional work could be done to further investigate small scale infiltration and volume control projects in the Kern Center Pond drainage area or downstream of the pond. 4 Emmons & Olivier Resources, Inc. 651 Hale Avenue North Oakdale, Minnesota 55128 memo coat. (T) 651.770.8448 (F) 651.770.2552 www.eorinc.com Table 1. Relative abundance of algae from Kern Center Pond. Five sampling sites were counted (up to the first 50 organisms per site) to calculate relative proportion of each genera. Genus Relative abundance Microcystis 90.26% Coelosphaerium 5.28% Anabaena 4.10% Anabaeno sis I < 1.0% Dinofla ellates < 1.0% Table 2. Su ey Coordinates and Elevations of Kern Center Pond Sites Northing Easting Elevation (ft.) (ft.) (ft.) Description SITE 1 POND 203367.051 494571.211 923.04 BOTTOM SITE 2 POND 203408.315 494607.862 922.19 BOTTOM SITE 3 POND 203513.423 494687.697 922.04 BOTTOM SITE 4 POND 203669.762 494808.926 921.54 BOTTOM SITE 5 POND 203768.293 494805.216 922.14 BOTTOM 203628.248 494611.124 935.188 1 RIM BEEHIVE Washington County Coordinates (86 adjustment) Emmons & Olivier Resources, Inc. 651 Hale Avenue North Oakdale, Minnesota 55128 memo coat. (T) 651.770.8448 (F) 651.770.2552 www,eorinc.com Figure 2. Site 1 core of Kern Center Pond Sediments � a x 6 e . le Site 1: • 16 cm. of sample • Roughly 1 cm. of flocculent • Predominately a Brown Silty Sand • A thin (less than 1 cm.) silty lens at the 3 cm. from bottom mark Emmons & Olivier Resources, Inc. 651 Hale Avenue North Oakdale, Minnesota 65128 c memo coat. (T) 651.7X 8448 (F) 651.770.2552 www.eorinc.coni Figure 3. Site 2 core of Kern Center Pond Sediments 4i i - KOO" Site 2: • 21 cm. of sample • Roughly 1 cm. of flocculent • Filamentous Algae • Predominately a Brown Silty Sand • A thin (less than l cm.) silty lens (located at visible crack around 19 cm. from bottom) Emmons & Olivier Resources, Inc. 651 Hale Avenue North Oakdale, Minnesota 55128 ' J memo cont. (T) 651.77€1.8448 (F) 651.770.2552 www,eorinc.com Figure 4. Site 3 core of Kern Center Pond Sediments Y'3 t r ' I I�II� ill S l�G 3 T 4'9 Site 3: • 21 cm. of sample • Roughly I cm. of flocculent • Filamentous Algae • Predominately a Brown Silty Sand • Silty lenses at approximately 1.5 cm. and 7 cm. from core bottom, these lenses are similar to lenses noted during excavation of Kern Pond in 2005. If laterally extensive, they may act as confining layers, but are most likely a reflection of cross- bedding planes that may slow vertical movement of water through the soil but not fully confine it (see Figure 11). Emmons & Olivier Resources, Inc. 651 Hale Avenue North Oakdale, Minnesota 55128 C memo Cont. --- (T)651. (F)651.770.2552 www.eoriiie.com Figure 5. Site 4 core of Kern Center Pond Sediments lC Site 4: - - • 23.5 cm. of sample • Roughly 1 cm. of flocculent • Filamentous Algae • Predominately a Brown Silty Sand Emmons & Olivier Resources. Inc. 651 Hale Avenue North Oakdale, Minnesota 55128 memo Cont. (T) 651.770.8448 (F) 651.770.2552 www.eorinc.corn Figure 6. Site 5 core of Kern Center Pond Sediments t 16 Site 5: • 31 cm. of sample • Roughly 1 cm. of flocculent • Filamentous Algae • Predominately a Brown Silty Sand • Sandy Silt lens from roughly l 1cm. to 16 cm. from bottom. If laterally extensive, it may act as a confining layer, but it is most likely a reflection of cross- bedding planes observed during pond reconstruction in 2005 that may slow vertical movement of water through the soil but not fully confine it (see Figure 11). Emmons & Olivier Resources, Inc. 651 Hale Avenue North Oakdale, Minnesota 56128 memo coat. (T) 651.770.8448 (F) 651.770.2552 www.eoritic.coni Figure 7. Grain Size Distribution Curve for select Kern Center Pond Sediments Grain Size Distribution ASTM D422 Job No.: 6710 Project: KeraCent.P.4 Testbate: gn11o6 Reported To: lEmmncens and Olivier Resources, Inc. Report Date: 9/15/06 Depth Sample Location / Boring No. Sample No. (cm) Type Soil Classification f Site 2 1 "l- 1 - Silty sand with or amts (SH site 5 31 - Silty sand SM O Site 1 To 1 cat 6a Silty sand with orgards (SN G ravel n Hydrometer Analysis Coarse Fine Coarse Medium Fine Fines 100 a gua N MW N xt • 90 i ... -. I • i _ 80 I 70 I 60 3 50 e 0 40 30 20 10 ~ 0 100 so z° 10 1 Crain S ze (m m) 0.1 os u 005 0.01 noz 0.001 Other Tests Percent Passing * • O s • O t • O Liquid Limit Mass (g) 44.0 177.1 20.7 Dso Plastic Limit 2" D. Plasticity Index 1.5" Dto Water Content 1" Cu Dry Density (pci) 3/4" Cc Specific Gravity 2.65` 2.65' 3/8" Remarks: Porosity #4 100.0 100.0 Organic Content 2.1 #10 100.0 100.0 PH #20 99.6 99.9 Shrinkage Limit #40 97.5 99.1 Penetrometer #100 78.4 1 62.0 Ou (p30 #2001 39.0 1 25.5 (• = ae umed) It_ 9301 Bryant Ave. South, Suite 107 Bloomington, Minnesota 55420 - 3436 H�3T[F£S3, INf'. 91 Emmons & Olivier Resources, Inc. 651 Hale Avenue North Oakdale, Minnesota 55128 memo Cont. (T)651.770.8448 (E')659.770.2552 www.eori!ic.com Figure 8. Microcystis colony from Kern Center Pond. The mucilagenous sheath is diminished by preservative (ETON). Photo: To ncois Figure 9. Coefosphaerium from Kern Center Pond. 10 Nm Photo: Toben Lafrancois \ Figure 10. Anabaena from Kern Center Pond. 10 pm A y, fv Photo: Toben Lafrancois A Emmons & Olivier Resources, Inc. 651 Hale Avenue North Oakdale, Minnesota 55128 memo cont. (T) 651.770.8448 (F)Wa 770.2552 www,eor9nc.cofn Figure 11. Cross Bedding and Vertical Fractures at Kern Center Pond during 2005 Pond Reconstruction r w f Emmons & Olivier Resources, Inc. 651 Hale Avenue North Oakdale, Minnesota 55128 FILE cagy- � � :- ......�� 1 r p w w CD o p x n a O `n 77 O [D a � Q m a m 0 Q v o CD rn 3 CD (D - m (7 Q CL co So m rn � a, n - '� e i k f o O p` Z3 Q s r Long Lake - 21)(in Lake t race • DNR ID #: 820021 • Municipality: City of Stillwater • Location: Section 30, T30N -R20W • Lake Size: 110 Acres • Maximum Depth: 22 ft �� y �� � >� • Ordinary High Water Mark: 891.50 ft ,. ���- :! • 100 -Year High Water Level: 893.20 ft • 95% Littoral I Note: Littoral area is the portion of the lake <15 ft and dominated by aquatic vegetation. o 4 wwow'sn.a I Long Lake a Summary Points • Long Lake was considered a eutrophic lake in 2008, based on the Carlson Trophic State Index. • There is a statistically significant improving trend for both average Secchi transparency and average total phosphorus. • The major land use is urban/residential. • The lake did stratify with the thermocline varying between 4 to 5 meters. • Long Lake is listed as impaired for nutrients on the Minnesota Pollution Control Agency's Impaired Waters List. Average SummerSurlace Total phosphorus Average Summer Secchi Transparency 0.18 --a--- Total Phosphorus 94 95 96 ° 98 90 00 01 02 03 04 05 06 07 08 09 0,00 — — TPYryairrnantThreshold 0.16 » Secchi Transparency 020 0.14 ,�. N ' 0.40 ,�♦ *�, ,� - 0.12 0.60 -7 E 2 0.10 H c 0.80 e a � f t m ►7 1.20 ..... ........................... ............................:.. hw;. 1.40 0.02 1.60 0.00 94 95 96 97 98 99 DO 01 02 03 04 05 06 07 08 09 1.80 2008 Water Monitoring Report —BCWD 101 -" Surface Dissolved Surface Total Total Kjeldahl Secchi Oxygen Temperature Phosphorus Chlorophyll -a Nitrogen Disk Levels Levels Date (mg /L) (ug /L) (mg /L) Depths (m) (mg /L) (Celsius) 4/22/2008 0.086 36 1.60 1.22 15.00 13.1 5/8/2008 0.064 26 1.80 1.52 9.87 14.9 5/21/2008 0.061 10 1.70 1.83 8.18 17.1 6/3/2008 0.053 6.8 1.60 2.74 7.58 19.7 6/18/2008 0.049 11 1.90 1.68 9.41 23.2 6/30/2008 0.055 16 2.40 1.37 9.37 24.4 7/16/2008 0.037 18 1.60 1.22 9.04 25.9 7/29/2008 0.059 47 2.40 11.48 29.1 8/13/2008 0.052 18 1.90 1.37 7.41 26.1 8/27/2008 0.050 20 2.50 1.52 7.88 23.2 9/8/2008 0.040 18 2.40 1.83 7.60 20.4 9/23/2008 0.046 19 1.60 1.98 8.25 20.9 10/10/2008 0.064 19 1.70 1.22 4.25 14.3 10/21/2008 0.034 25 1.60 1.37 9.35 12.4 2008 Average 0.054 1 21 1.91 1 1.56 1 8.91 1 20.3 2008 Summer Average 0.049 19 2.03 1.63 8.67 23.7 Water quality thresholds are 0.04 mg /L TP, 14 pg /L CL -a, 1.4 m Secchi depth' Shallow lake water qualit thresholds are 0.06 mg /L. TP, 20 ug /L CL -a, 1,0 m Secchi depth* High High Date Low Low Date Average 2008 Elevation (it) 1 890.05 4/22/2008 889.03 6/7/1902 889.65 •MPCA description of Imparted Lake's Listing criteria: "At a minimum, a decision that a given lake is impaired for the 303(d) list due to excessive nutrients will be supported by data for both causal and response factors. Data requirements for 303(d) listing consist of 12 or more TP measurements collected from June through September over the most recent 10 -year period. Ideally this should represent 12 separate visits to the lake over the course of two summers; however it might also reflect four monthly samples over the course of three years (a typical sampling regimen for many lake monitoring programs). In addition to exceeding the TP guideline thresholds, lakes to be considered for 303(d) listing should have at least 12 Secchi measurements and 12 chlorophyll -a measurements. This amount of data will allow for at least one season (preferably more) for paired TP, chlorophyl -a, and Secchi disk data and provide a basis for evaluating their interrelationships and hence the tro hic status of the lake." Lake Bevation 892.0 o- �- Bevetion 891.5 .... ............................... ea1 ................................................................... ............................... ................... 890.5 ...... ............................... . ........ ..................:....... .......................................................... C 890.0 .............. .................... ...................................................:................ ............................... 889.5 .................. ............................... ..... ........, ...... ...... ..,..,........ ............................... 889.0 .......................................... ............................... ............................... 888.5 4/12/18 8/1/08 7/21/08 9/9108 10/29/08 12/18/8 Lake Water Quality Summary Trophic Status Summertime Lake Grades 2008 2008 2007 2006 2005 2004 2003 2002 2001 2000 1999 1998 1997 1996 1995 Total Phosphorus (mg/l) Eutrophic C C D D D D D D- F D D NA D D Chlorophyll - (ugA) Eutrophic B C C D C D- F+ F F F F NA D D Secchi disk ($) Eutrophic C D D F C- F F F F F F F F+ F+ Overall Eutro hic I C+ C- D+ D- C- D- F F F F F F D- D- 2008 Water Monitoring Report -BCWD 102 F ILE COPY Oak Park Heights Request for Council Action Meeting Date July 28 2009 Time Required: 5 Minutes Agenda Item Title: Public Works Director: Appoint Interim Director & Initiate Search Process. Agenda Placement New Business Originating Department/Request'or�.. ` ``Er' Johnson Ci Administrator Requester's Signature Action Requested Please see tacked memo Background /Justification (Please indicate if any previous action has been taken or if other public bodies have advised): Please see attached memo. f , City of Oak Park Heights 14168 Oak Park Blvd. N • Box 2007.Oak Park Heights, MN 55082 • Phone (651) 439 -4439 • Fax (651) 439 -0574 July 28th, 2009 MEMO TO: City Council Members FROM: Eric Johnson, City Admmitrgt RE: Interim Director of Public WorksyJ Initiate Recruitment Process for Public Works Director. With the vacancy in the public works director positiop City must move forward on two fronts: 1. Appoint an interim person to lead the department during this transition period between Directors perhaps 60 to 120 days. I would at this point offer that Mr. Andrew Kegley be appointed to such position. During his five -year tenure with the City he has been consistently positive, follows through on assigned tasks and responds to questions. He does not have extensive experience in the "field" compared to other veterans, but I believe his demonstrated work ethic would be an asset during the transition period and should he have certain questions he would know to ask other staff and /or the engineer's office. He would only be expected to deal the day -to -day issues and not delve too deeply into complex matters such as capital improvements or budgetary preparation. At this time the Public Works Department must focus on effective general operation and health and safety issues. We would hold regular review meetings with Mr. Kegley to better assure his effectiveness in this role. Mr. Kegley must retake his water - operator's test (Class D) in September as his current license has expired. With this increased responsibility, there should be a commensurate pay increase during this period. This wage should be above the Crew Foreperson's salary of $56,642 but slightly below the starting wage of a new inexperienced public works director being $58,594. Accordingly I would suggest that amount be $58,000 and is $9,257 more than his current base salary. These funds will be available from the 2009 budget as the City will not be paying the full Public Works Director position for approximately 12 weeks. REQUESTED ACTION: Appoint Mr. Andrew Kegley as Interim Public Works Director at annualized wage of $9,257.00 and that this appointment shall remain in effect as determined by the City Administrator or until a new Public Works Director is hired. (Mr. Kegley would return to his crew position at the end of this hiring process) 2. Initiate a hiring process; with the City Council's permission I would like to initiate the process to seek and appoint a new Public Works Director. Ideally we would have someone in place before Thanksgiving. Anticipated Process: 1. Appoint Director of Public Works Review Committee (two City Council Members, one public works staff member, city administrator, outside /retired public works director) (August 2009) 2. Review I revise job description (August 2009) 3. Advertisement 1 Solicit for Applications (August 1 September 2009) 4. Screening of Applications (September 2009) 5. Hold V Round of Interviews with Committee (September 2009) 6. Finalists would interview with entire City Council 1 Selection Made. October 2009 7. Commence Work. Late October 1 Early November. The estimated cost of the search will be approximately $5,000 +1- with costs for advertising, documents, possible legal review of contracts, etc. REQUESTED ACTION: Approve and initiate hiring process as above; appoint two City Council members to the Director of Public Works Review Committee. City of Oak Park Heights Bills Presented for Payment July 28, 2009 Payroll Gross Payroll with PERA, FICA, and Medicare City Administration: 8,811.45 7 -31 -09 Part-Time 7 -16 -09 516.72 Finance: 7 -31 -09 9,442.95 Police Department: 30,022.85 7 -31 -09 Building Inspection Department: 4,741.41 7 -31 -09 Public Works- Street Maint. Department: 7 -31 -09 712.01 Part-Time 7 -15 -09 0.00 Park and Recreation Department: Full -Time 7 -31 -09 1,717.61 Part-Time 7 -15 -09 1,523.79 Total 3,241.40 Water Department Full -Time 7 -31 -09 4,835.72 Sewer Department Full -Time 7 -31 -09 3,118.27 Storm Sewer Department Full -Time 7 -31 -09 630.72 Total Utility Fund 8,584.71 Total Payroll 66,073.50 Page: 1 CITY OF OAK PARK HEIGHTS Check Register - Council Report Jul 28, 2009 04:13pm Check Issue Date(s): ALL - ALL Report Criteria: Check.lnput Date = 07/15/2009- 07/28/20 Check.GL Invoice Acct (3 Characters) _ { < >} 901 Invoice Description Inv Amount Date Check No Payee 250.00 07/21/2009 51208 CINDY'S CREATIVE CELEBRATIONS FACE PAINTING & BALLOONS -PIP 8/4/09 2 786.00 M 07/21/2009 72120093 REVENUE, MN DEPT OF SALES & USE TAX - JUN09 23.33 - M 07/23/2009 51105 VOID - MINNESOTA'S BOOKSTORE RESIDENTAL & COMMERCIAL ENERGY CODE 868.36 07/23/2009 51210 MIDWEST PARTY RENTAL INC CANOPY TENT RENTAL - PARTY IN THE PARK 15.00 07/23/2009 51212 10000 LAKES CHAPTER MN ENERGY CODE SEMINAR 7/30/09 ZING RING FLIER, KRYPTON PENS 448.44 07/23/2009 51213 41MPRINT 138.94 07/23/2009 51214 ACTION RENTAL CONCRETE TRAILER RENTAL DINGO RENTAL 196.03 DINGO RENTAL 187.03 BOBCAT EXCAVATOR RENTAL 229.78 751.78 Total 51214 UNIFORM - KELLOGG 74.46 07/23/2009 51215 ARAMARK 176.88 07/23/2009 51216 AREA WIDE TOWING TOW FORFEITURE VEHICLE PREMIUM - JUL 710.15 07/23/2009 51217 ASSURANT BENEFITS 514.00 07/23/2009 51218 BELSON OUTDOORS INC PET WASTE SYSTEMS WITH LID 4,123.66 07/23/2009 51219 BONESTROO ROSENE ANDERLIK ENGINEERING SERVICES 5/24 - 6/27/09 13,020.50 07123/2009 51220 BRAUN INTERTEC CORP CITY HALL CONCRETE TESTING 15.00 07/23/2009 51221 BUBERL RECYCLING & COMPOS INC YARD WASTE 64.63 07/2312009 51222 CLOUTIER, CALVIN REIMB FOR MILEAGE 6/26 - 7/12 REIMB FOR MILEAGE 7113 - 7/26 45.38 110.01 Total 51222 WATER COOLER RENTAL USE TAX 76.52 07/23/2009 51223 DEEP ROCK WATER CO E WELLNESS SEMINAR 80.00 WORKPLACE 07/23/2009 51224 EMBODIED HEALTH LLC 20.00 07/23/2009 51225 FRED'S TIRE CO INC TIRE REPAIR WATER CONNECTIONS - 2ND QTR 2,.00 169 07/23/2009 51226 HEALTH, MN DEPT OF 169.93 07/23/2009 51227 HELMER PRINTING INC TOW IN FORMS IACP TRAINING KEYS - 9 SUBSCRIPTIONS 107.00 07/23/2009 51228 IACP 425.00 07/23/2009 51229 IFP TEST SERVICES POLICE OFFICER PSYCH EXAM 2, 017.41 07/23/2009 51230 LABOR & INDUSTRY, MN DEPT OF SURTAX - 2ND QTR 2009 413.76 07/23/2009 51231 LHB INC TIF PROF SERVICES - JUN PREMIUM AUG 487.00 - 07/2312009 51232 LINCOLN MUTUAL 87 78 07/23/2009 51233 MENARDS - STILLWATER REBAR, SPRAY PAINT SCRAPERS & TOP SOIL - BREKKE PARK 29.87 PARK SUPPLIES - VALLEY VIEW 64.64 72.77 RAKES 255.06 Total 51233 2,450.00 07/23/2009 51234 MILLER EXCAVATING INC. INSTALL DRAINTILE - VALLEY VIEW 39,031.00 ARK 07/23/2009 51235 MINNESOTA /WISCONSIN PLAYGROUN PT I ME PLAY STRUCTURE - VALLEY VIEW POWER CAR WASH SOAP 10.67 07/23/2009 51236 NAPA AUTO PARTS 68.66 07/23/2009 51237 NEXTEL COMMUNICATIONS CELL PHONE 6/13 - 7/12/09 38.72 07/23/2009 51238 OFFICE DEPOT PAPER CARTRIDGES 427.39 466.11 Total 51238 119.23 07/23/2009 51239 OFFICE MAX INC MOUSE PAD M = Manual Check, V = Void Check 1 Check Register - Treasurer's Report Page: 1 CITY OF OAK PARK HEIGHTS g Jul 28, 2009 03:28pm Check Issue Date(s): ALL - ALL Report Criteria: Check.lnput Date = 07/15/2009- 07/28/2009 Check.GL Invoice Acct (3 Characters) _ {_} 901 Date Check No Payee Invoice Description Inv Amount 07/17/2009 71720091 SMITH BARNEY CITIGROUP PURCHASE SMITH BARNEY MONEY MARKET 3,332.38 M 07/21/2009 51209 OAK PARK HEIGHTS, CITY OF PURCHASE 4M FUNDS 111,000.00 07/21/2009 72120091 SMITH BARNEY CITIGROUP PURCHASE SMITH BARNEY MONEY MARKET 917.02 M 07121/2009 72120092 NORTHLAND SECURITIES INC PURCHASE NORTHLAND MONEY MARKET 201.37 M 07/23/2009 51211 OAK PARK HEIGHTS, CITY OF PURCHASE 4M FUNDS 280,000.00 07/24/2009 72420091 NORTHLAND SECURITIES INC PURCHASE NORTHLAND MONEY MARKET 151.03 M 07/28/2009 72820091 NORTHLAND SECURITIES INC PURCHASE NORTHLAND MONEY MARKET 711.82 M 396, 313.62 Totals: M = Manual Check, V = Void Check