Blue Earth River Basin Fecal Coliform TMDL Study

Transcription

1 Blue Earth River Basin Fecal Coliform TMDL Study What is fecal coliform bacteria? Fecal coliforms are bacteria that live in the digestive tract of warmblood animals (humans, pets, farm animals, and wildlife) and are excreted in the feces.

2 Waterborne Pathogens Giardia A microscopic protozoan parasite that lives in the intestine of people and animals. There are approximately 970 to 1550* cases of giardiasis reported to the MN Department of Health each year. Cryptosporidium Cryptosporidiosis (often called Crypto ) is a diarrheal disease caused by the protozoan parasite Cryptosporidium spp. Approximately * cases of Crypto are diagnosed in Minnesota each year. * statistics reflect reported foodborne and waterborne sicknesses Source: MN Department of Health Streams in southern Minnesota have significantly higher bacterial levels than northern Minnesota streams.

3 Blue Earth Watershed % Samps. Apr. May Jun. Jul. Aug. Sep. Oct. Site ID >2000 Center Creek, 315 Ave. Elm Creek, 290th Ave. Dutch Creek, 100th St. Blue Earth River, Mankato Lily Creek, Hunt Farm Elm Creek, 185th St. Cedar Run, S34/35 Judicial Ditch #3 Center Creek, S34/35 Cedar Run, CSAH 9 Center Creek, George Lake Elm Creek, 260th Ave. Blue Earth River, Rapidan Blue Earth River, CSAH 4 Elm Creek, CSAH 149 Blue Earth River, CR 10 East Branch Blue Earth River Elm Creek, Township Road Blue Earth River, CR 6 Blue Earth River, CR 34 Blue Earth R at SH-30 Exceeds Surface Water Standard (Impaired) Meets Standard

4 Le Sueur Watershed % Samps. Apr. May Jun. Jul. Aug. Sep. Oct. Site ID >2000 Beauford Ditch Maple River CSAH 35 Little Cobb River Le Sueur, Near Rapidan #1 Le Sueur, Near Rapidan #2 Watonwan Watershed % Samps. Apr. May Jun. Jul. Aug. Sep. Oct. Site ID >2000 Watonwan River, Garden City Watonwan River, CR 6 Watonwan River, CSAH 4 Watonwan River, Madelia Watonwan River, CR 16 Exceeds Surface Water Standard (Impaired) Meets Standard Load Allocation Process Load limits were calculated for each impaired stream, based on five flow regimes. Wasteload was allocated to legal dischargers, which are WWTP s and cities with MS4 stormwater permits. Feedlots with NPDES permits and straight pipe septics systems are allocated zero load. Load allocation includes all non-point sources (wildlife, livestock manure, stormwater, etc). A portion of the allowable load is allocated to a margin of safety.

5 TMDL Load Allocation Example Blue Earth River, Mankato Blue Earth River, Mankato Drainage Area (square miles): 3,540 USGS gage used to develop flow zones and loading capacities: BE River, USGS Site % MS4 Urban: 1% Total WWTF Design Flow (mgd): Flow Zone High Moist Mid Dry Low values expressed as trillion organisms per month (T-org./month) TOTAL MONTHLY LOADING CAPACITY Wasteload Allocation Permitted Wastewater Treatment Facilities Communities Subject to MS4 NPDES Requirements Livestock Facilities Requiring NPDES Permits "Straight Pipe" Septic Systems Load Allocation Margin of Safety values expressed as percent of total month loading capacity TOTAL MONTHLY LOADING CAPACITY 100% 100% 100% 100% 100% Wasteload Allocation Permitted Wastewater Treatment Facilities 0.3% 0.6% 1.2% 3.8% 25.6% Communities Subject to MS4 NPDES Requirements 0.4% 0.4% 0.4% 0.3% 0.2% Livestock Facilities Requiring NPDES Permits 0.0% 0.0% 0.0% 0.0% 0.0% "Straight Pipe" Septic Systems 0.0% 0.0% 0.0% 0.0% 0.0% Load Allocation 78.4% 76.4% 72.3% 55.3% 37.9% Margin of Safety 20.9% 22.5% 26.1% 40.6% 36.3% TMDL Wasteload and Load Allocations Example Blue Earth River, Mankato Blue Earth River, Mankato TMDL Allocation for "High" flows Margin of Safety 20.90% Permitted Wastewater Treatment Facilities 0.24% Communities Subject to MS4 NPDES Requirements 0.42% Load Allocation 78.44% Livestock Facilities Requiring NPDES Permits 0.00% "Straight Pipe" Septic Systems 0.00% Livestock Facilities Requiring NPDES Permits 0.00% "Straight Pipe" Septic Systems 0.00% Blue Earth River, Mankato TMDL Allocation for "Low" flows Margin of Safety 36.33% Load Allocation 39.01% Permitted Wastewater Treatment Facilities 24.45% Communities Subject to MS4 NPDES Requirements 0.21%

6 Targeted Sources The following slides describe the procedure used to estimate the primary sources of fecal coliform contamination in impaired streams. This procedure has no bearing on TMDL allocations and has no regulatory implications. Step 1: The first step was to estimate the amount of fecal material generated in the Basin using populations inventories. Fecal Coliform (FC) Organisms Animal Produced Per Individual Total FC Animal Type Units Individuals or AU Per Day Available Source (Daily FC Produced) Dairy 39, E E+15 ASAE*, 1998 Beef 92, E E+16 ASAE, 1998 Swine 554, E E+16 ASAE, 1998 Chicken 7, E E+14 ASAE, 1998 Turkey 9, E E+13 ASAE, 1998 Horse E E+11 ASAE, 1998 Sheep 1, E E+14 ASAE, 1998 Humans 92, E E+14 Metcalf and Eddy, 1991 Cats 25, E E+14 Horsley and Witten, 1996 Dogs 22, E E+14 Horsley and Witten, 1996 Deer 12, E E+12 Interpolated from Metcalf and Eddy, 1991 Canadian Geese 15, E E+08 Alderisio and DeLuca, 1999 Wild Turkey 3, E E+11 turkey value used Pheasants 100, E E+09 geese value used Other Wildlife** 6.37E+12 * American Society of Agricultural Engineers ** Unknown, estimated to be roughly the equivalent of the deer population. Estimated Fecal Coliform Produced by Animal Type Sheep 0.46% Horse 0.00% Turkey 0.10% Chicken 0.45% Dogs 0.18% Cats 0.21% Humans 0.31% Deer 0.01% Canadian Geese 0.00% Wild Turkey 0.00% Pheasants* 0.00% Other Wildlife** 0.01% Dairy 4.70% Beef 19.95% Step 2: Estimate fecal material produced by animal type. Estimated Fecal Coliform Produced by Source Group Humans, 0.31% Pets, 0.39% Wildlife, 0.02% Livestock, 99.28% Swine 73.62%

7 Step 3: Where does it go? Category Source Assumptions* Animal Units or Individuals Livestock Overgrazed Pastures near Streams or Waterways 1% Dairy Manure 393 Dairy AU 1% Beef Manure 925 Beef AU 1% Horse Manure 8 Horse AU 1% Sheep Manure 14 Sheep AU Feedlots or Manure Stockpiles without Runoff Controls 1% of Dairy Manure 393 Dairy AU 5% of Beef Manure 4,623 Beef AU 1% of Chicken Manure 79 Chicken AU 1% Turkey Manure 98 Turkey AU Surface Applied Manure 49% Dairy Manure 19,248 Dairy AU 47% Beef Manure 43,454 Beef AU 20% Swine Manure 110,868 Swine AU 49.5% Horse Manure 396 Horse AU 49.5% Sheep Manure 692 Sheep AU 49.5% Chicken Manure 3,912 Chicken AU 49.5% Turkey Manure 4,868 Turkey AU Incorporated Manure 49% Dairy Manure 19,248 Dairy AU 47% Beef Manure 43,454 Beef AU 80% Swine Manure 443,471 Swine AU 49.5% Horse Manure 396 Horse AU 49.5% Sheep Manure 692 Sheep AU 49.5% Chicken Manure 3,912 Chicken AU 49.5% Turkey Manure 4,868 Turkey AU Human Human - Inadequately Treated Wastewater 14.33% of Human 13,213 Humans Rural Population - Unsewered Communities 2.94% of Humans 2,719 Humans Human - Adequately Treated Wastewater 22.67% of Humans 20,900 Humans Municiple Wastewater Treatment Facilities 60.05% of Humans 55,370 Humans Pets Pets 100% of Cats 25,043 Cats Dogs 100% of Dogs 22,007 Dogs Wildlife Canadian Geese 100% of Canadian Geese 15,771 Canadian Geese Deer 100% of Deer 12,744 Deer Wild Turkey 100% of Wild Turkey 3,859 Wild Turkeys Pheasants 100% of Pheasant 100,000 Pheasant Other Wildlife Unknown (est. as deer pop.) Unknown (est. as deer pop.) *Assumptions used for livestock were obtained from the Generic Environmental Impact Statement on Animal Agriculture prepared by the Minnesota Environmental Quality Board. Targeted Sources Step 3: Where does it go? The total fecal material available was categorized by source or application type. Estimated Fecal Coliform Produced by Source / Application Type (based on GEIS assumptions) Pets 0.39% Human - Adequately Treated Wastewater 0.25% Human - Inadequately Treated Wastewater 0.05% Wildlife 0.02% Overgrazed Pastures near Streams or Waterways 0.25% Feedlots or Manure Stockpiles without Runoff Controls 1.05% Surface Applied Manure 26.90% Incorporated Manure 71.08%

8 Targeted Sources Step 4: What is delivered to waterways? Delivery ratios, based on expert opinions were used to estimate the amount of fecal coliform bacteria that could runoff into streams. Category Source April/May (Wet) April/May (Dry) Summer (Wet) Summer (Dry) Livestock Overgrazed Pastures near Streams or Waterways 4.0% 1.0% 4.0% 1.0% Feedlots or Manure Stockpiles without Runoff Controls 4.0% 2.0% Surface Applied Manure 1.0% 1.0% Incorporated Manure 0.1% Human Rural Population - ISTS that are an Imminent Public Health Risk 8.0% 8.0% 8.0% 8.0% Rural Population - Unsewered Communities 8.0% 8.0% 8.0% 8.0% Rural Population - ISTS that are not an Imminent Public Health Risk Municiple Wastewater Treatment Facilities Pets Cats/Dogs 0.5% 0.5% Wildlife Canadian Geese 4.0% 4.0% 4.0% 4.0% Other Wildlife 1.0% 1.0% 1.0% 1.0% Targeted Sources Step 5: Primary sources of fecal coliform bacteria pollution to waterway. Using the delivery ratios in step 3 the primary contributors of fecal coliform contamination are estimated. Major Contributors of Fecal Coliform Bacteria by Flow Condition Category Source Wet Conditions Dry Conditions Livestock Overgrazed Pastures near Streams or Waterways Low Contributor Moderate Contributor Feedlots or Manure Stockpiles without Runoff Controls Moderate Contributor Low Contributor Surface Applied Manure High Contributor Low Contributor Incorporated Manure Moderate Contributor Low Contributor Human Human - Inadequately Treated Wastewater Low Contributor High Contributor Pets Cats & Dogs Low Contributor Low Contributor Wildlife Deer, Canadian Geese, Wild Turkeys, Pheasants, etc. Low Contributor Low Contributor This example shows the primary contributors of fecal coliform contamination for the Blue Earth River, at Mankato.

9 Human Sources Category Population Percent Rural - ITPHS 14, % Unsewered Communities % Rural - not ITPHS 22, % WWTPs 54, % Total Pop 92,202 Septic systems that are an imminent threat to public health and safety (including unincorporated unsewered communities). 36,832 people x.39% ITPHS) = 14,364 humans 14,364 humans / 2.43 per household = 5,911 ITPHS systems 5,911 systems / 3540 sq. miles = 1.7 ITPHS systems per square mile Incorporated Unincorporated Community County Population Community County Population Walters Faribault 82 Rapidan Town Blue Earth 250 Lasalle Watonwan 96 Garden City Blue Earth 230 Ormsby Watonwan 152 Guckeen Faribault 36 Odin Watonwan 95 Huntley Faribault 91 Ledyard Kossuth 258 Bergen Jackson 10 Lakota Kossuth 255 Fish Lake Jackson 115 Total Incorporated 938 Village Of East Chain Martin 48 Village Of Immogene Martin 22 Village Of Fox Lake Martin 25 Elk's Park/Lakeview Rst Waseca 25 Rolling Greens Waseca 30 Fairway Acres Waseca 60 Otisco Waseca 45 Smiths Mill Waseca 31 Alma City Waseca 25 Matawan Waseca 48 Reeds Lake Waseca 65 St. Olaf Lake Waseca 53 East Lake Elysian Subd. Waseca 58 Grogan Watonwan 35 South Branch Watonwan 30 Long Lake Watonwan 200 Total Unincorporated 1532 Total Unsewered Incorporated and Unincorporated 2470

10 WWTP Bypasses Emergency bypass of partially or untreated wastewater, usually due to overloading during heavy precipitation. 38 reported from Typically last a few hours to few days. Cities with >2 bypasses from : Blue Earth (7), Winnebago (3), Elmore (3) (Bypasses from these three communities are all directly into the Blue Earth River.) WWTP Violations WWTPs must test fecal coliform levels weekly. The geometric mean of all samples collected in a month must not exceed 200 org/100 ml. 23 violations reported from of these violations from three communities, Truman (7), Waldorf (5) and Mountain Lake (2).

11 Livestock Blue Earth River Basin Livestock (% Total) Sheep 0.2% Chicken Turkey 1.1% 1.8% Dairy 5.4% Beef 13.3% Swine 78.2% Livestock Type (Percentage of Total) Dairy Beef Swine Sheep Chicken Turkey Note: Minnesota and Iowa feedlot inventory databases vary significantly. The Iowa feedlot inventory only includes larger feedlots that were available in GIS format. Thus, feedlot values for Iowa counties are skewed lower than Minnesota Counties. Livestock Manure Livestock density is shown by minor Watershed. Gray areas represent permitted manure spread fields in Faribault County. 98% of all fecal material in the Basin is associated with livestock manure that is applied to cropland as a fertilizer.

12 How Does Manure Reach Surface Waters? Surface Runoff Open Intakes Macropores / Preferential Flow Surface Runoff and Open Intakes Surface runoff and open intakes can be routes of transport of manure from applied lands. Observance of manure application setback rules are crucial.

13 Macropores In Ohio, Shipitalo and Gibbs pump smoke into a tile line to show the connectivity of the surface to tile line. In Ohio, macropores are a major pathway of fecal transport in tiled lands. In Minnesota, it is not well understood to what magnitude macropores have on bacterial transport. Earthworm densities are less in Minnesota than Ohio. Soil types may also be different. Researchers stress that macropores are greatly influenced by tillage. No till and conservation tillage which help reduce soil erosion may have the negative effect of leaving macropore pathways open to tile tiles. Macropores may help explain high fecal concentrations monitored from tile outlets after moderate/heavy precipitation. Work by the Agricultural Resource Service (USDA) Martin Shipitalo in Ohio have traced macropores made by earth worms from the surface to 4 feet deep. The pictures depict a conventionally tilled, clayey soil where earthworms appear to preferentially burrow towards the drains. The tile in this photo is 4 feet deep. The main processes which contribute to the formation of macropores in natural soils include: Pores formed by soil fauna such as earthworms, insects, mole and gophers. Crack and fissures formed during the shrinkage of clay soils and freeze/thaw cycles. Pores formed by plant roots. Natural soil pipes that form due to erosive action of subsurface flows.

14 Factors that are Associated with Fecal Coliform Levels in Streams Temperature relationship Storm event vs. baseflow Fecal Coliform Concentrations and Temperature % Samples Exceeding 200 cfu/100 ml 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Beauford Creek Watershed Fecal Coliform Bacteria Concentration vs. Stream Temperature 2000, 2004 and 2005 Monitoring Data (excluding samples taken within 48 hours of >.5 inch rain.) 33% 53% 91% <50F 50-60F >60F Temperature (f)

15 Fecal Coliform Concentrations and Temperature Beauford Creek Watershed Fecal Coliform Bacteria Concentration by month 2000, 2004 and 2005 Monitoring Data (excluding samples taken within 48 hours of >.5 inch rain.) Fecal Coliform Geometric Mean (orgs/100 ml) March April May June July August September Month Fecal Coliform and Runoff Beauford Watershed Flows and Fecal Coliform Concentrations Peak Flow 300 CFS Samples collected in April/May have much lower FC levels than summer/fall samples. Flow (cfs) ,000 Concentrations are much higher during storm runoff. The greater the intensity of precipitation, the higher the FC concentrations. 130,000 13,500 Date FC 40 7/7 1, / / /19 1, ,000 7/21 1,040 7/26 6, ,600 8/ , , ,100 1, /2 3/8 3/14 3/20 3/27 4/2 4/8 4/14 4/21 4/27 5/3 5/9 5/16 5/22 5/28 6/3 6/10 6/16 6/22 6/28 7/5 7/11 7/17 7/23 7/30 8/5 8/11 8/17 8/24 8/30 9/5 9/11 9/18 9/24 9/30 Date

16 Beauford Watershed Research Project This 5,500 acre minor watershed is located in the Le Sueur major watershed. The minor has been monitored on again/off again since 1994 for fecal coliform bacteria. The watershed was the focus of an ISTS upgrade project in 1994/1995. Beauford Watershed 2005 Landuse Landuse Category Acres Percent Cultivated Land 4, % Grass/Shrub/Tree % Grassland % Roads % Urban/Rural Development % Water % Bog/Marsh 4 0.1% Woodland/Forest %

17 In 1994 and of 32 septic upgrades were completed in the watershed. 28 of the 42 (66%) septic systems in Beauford are permitted since (83%) systems are permitted. Improvement seems to have occurred, but fecal levels remain high. (Difficult to compare results because most low flow samples collected prior to septic upgrades were in March and November, out of the monitoring season.)

18 Beauford Watershed Water Quality Improvements? Beauford Creek Watershed Low Flow Samples (less than 5 CFS) collected between 1994 and 2005 Sample Linear (Sample) Fecal Coliform (cfu/100 ml) cfu/100 ml Jan-93 Jun-94 Oct-95 Mar-97 Jul-98 Dec-99 Apr-01 Sep-02 Jan-04 May-05 Oct-06 Fecal Coliform Geometric Means Samples Grouped by Monitoring Years Years FC # Samples % Smpls >200 94/ % 96/ % 98/ % % % Table represents analysis of low flow samples (<5 CFS). Date In the fall of 1995, 18 of 32 septic systems were upgraded in the Beauford watershed. As of 2005, 35 of 42 systems in the watershed were permitted. Trend analysis shows a decrease in fecal coliform bacteria concentrations during low flow conditions. While there is an apparent reduction in FC after upgrades in 1995, it should be noted this is based on a small data set. Since 1996 there is no significant trend in fecal coliform levels. A signicant percentage of samples during low flow periods still are high in fecal coliform concentration. The highest bacterial concentrations during low flow occur in the later summer months (July, August). Why do fecal levels remain high during low flow periods in the Beauford Creek Watershed? Fecal Coliform Bacteria Date Site B1 Site B3 Site B4 3/9/ /24/ /29/ /7/ /15/ /21/ /28/ /4/ /9/ /10/ /12/ ,500 1, /13/2005 1,200 1,000 4,500 5/18/ /19/ /23/ /31/ /1/ /8/2005 9,000 1,300 10,000 6/15/ ,625 6/22/ /29/ /30/2005 1, /7/2005 1, ,000 7/11/ /13/ ,100 7/19/2005 1, ,000 7/21/2005 1,040 7/26/2005 6,000 2,400 1,700 8/3/ ,600 1,200 8/10/ ,000 8/16/ /18/ , /26/ ,000 6,000 5,200 9/8/2005 2,100 9/15/2005 1,500 1,800 9/22/ /24/ ,000 9/25/ ,000 9/26/ ,000 11,000 60,000 10/6/2005 1, ,900 10/20/ /27/ , Monitoring Results for Beauford Watershed 71% (71 of 101) samples collected from April through October exceeded 200 org/100 ml. 89% (59 of 66) samples collected from June through October exceed 200 org/100 ml. Surface water standard exceeded in May, June, July, August and September (not enough samples collected in October).

19 Sediment as a Reservoir of fecal coliform Sediment and water column samples were collected from three sites in Beauford Creek Watershed on 16 occasions. The north ditch had a sandy bottom, the south branch a rich black mud and the outlet a mixture of the two. Site B1 (outlet) Site B3 Site B4 Sediment as a Reservoir of fecal coliform Fecal coliform concentrations were tens to hundreds times higher in the sediment samples than the water column samples. This corresponds with other sediment/water column sampling that has taken place in the US. Mud/Sand Sand Mud

20 Sediment as a Reservoir of fecal coliform Stream bottom soil type was correlated with fecal coliform concentration. There was a strong relationship between fecal coliform in the stream sediment compared to that in the water sample. Site ID Sediment Type Sediment Water(<5 CFS) Site B1 (outlet site) Sand/Mud Bottom Site B3 (north branch) Sand Bottom Site B4 (south branch) Mud Bottom Sediment vs. Water (Baseflow) Average Fecal Coliform Concentration Sediment Water Site B1 (outlet) Site B3 (north) Site B4 (south) Sediment as a Reservoir of fecal coliform Elevated fecal concentrations during low flow periods may be partially attributed to streambed sediments that become saturated with fecal bacteria after storm events.

21 Sediment as a Reservoir of fecal coliform Groundwater discharge to ditches and streams may release fecal coliform bacteria into the water column.

22 On September 25 th, 2006 we had the highest bacterial levels ever monitored in the Beauford watershed. Fecal coliform levels were 130,000 cfu/100 ml at the outlet after 4+ inches. The last observance of manure application was in the middle of May. These high levels seem indicative of what other research has shown, fecal bacteria able to live for long periods in soils.

23 Timeline for Final Report March 2006 Draft Completed April, May, June Comment Period June 30 th Final Report Due