ASCE - Philadelphia. Soils & Stormwater Management. Matthew C. Hostrander, CPSS, SEO Soil Scientist. Gilmore & Associates, Inc.

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1 ASCE - Philadelphia Soils & Stormwater Management Matthew C. Hostrander, CPSS, SEO Soil Scientist Gilmore & Associates, Inc.

2 Course Overview COURSE OUTLINE Soil Science Fundamentals Discuss United States Department of Agriculture (USDA) soil classification in the field, as well as briefly review the Unified Soil Classification System (USCS) classification system and its differences from the USDA system. Review standard deep-hole test pit logging procedures. Soil Water Characteristics and Behavior Examine the movement of water, or lack there of, in relation to specific soil features and properties. Soils & Stormwater Engineering So, why stormwater management? In this section we will discuss the importance of stormwater management and the start to finish process to developing a successful BMP. Web Soil Survey Tutorial Online resources continue to improve - the official soil survey is available on the USDA National Resource Conservation Service website, known as the Web Soil Survey (WSS).

3 Soil Science Fundamentals Soil classification and profile descriptions United States Department of Agriculture (USDA) versus Unified Soil Classfication System (USCS) classification systems Soil forming factors Rock depth and drainage classification General deep-hole test pit log methods

4 Soil Science - USDA Soil Profile Horizons Soil Color Soil Texture Soil Structure Wet Soil Consistence Redoximorphic Features (Mottling)

5 Soil Profile Horizons O Layers dominated by organic matter (e.g. forest leaf litter layer). A Mineral horizon formed at the surface or below an organic horizon. These horizons are typically topsoil layers. E Mineral horizon in which the dominant feature is the eluvial loss of clay, iron, aluminum, or organic matter. These losses result in a concentration of sand and silt particles and lighter colors. B Horizons that formed below an A, E, or O horizon and are dominated by obliteration of all or much of the original rock structure and show one or more of the following: illuvial concentration of silicate clay, iron, aluminum, humus, carbonates, or silica; evidence of removal of carbonates; residual concentration of sesquioxides; and brittleness. C Mineral horizons that are relatively unaffected by soil-forming processes. Properties are dominated by the parent material. Unconsolidated with low to moderate excavation difficulty, but is still considered soil. R Hard bedrock that is difficult to excavate.

6 Soil color should be documented using the Munsell color charts, and utilize Hue, Value, and Chroma. The matrix color of each horizon should be described. Changes in color may often provide important information about a particular soil horizon. Soil Color

7 Soil Texture Soil texture refers to the weight proportion of the sand, silt, and clay particles that are 2 mm and less. The percentages of these mineral particles determines the texture of the soil. Rock modifiers are added for percentages of rock fragments in a given horizon.

8 Soil Texture Clay, Clay Loam, Loam, Sandy Clay, Sandy Clay Loam, Sandy Loam, Coarse Sandy Loam, Fine Sandy Loam, Very Fine Sandy Loam, Loamy Sand, Loamy Coarse Sand, Loamy Fine Sand, Loamy Very Fine Sand, Sand, Silty Clay, Silty Clay Loam, Silt Loam, Silt

9 Soil Texture Modifiers for Percent Rock Fragments Gravelly, Channery, Flaggy, Stony, Bouldery Example: 0-15% - None 15-35% - Gravelly 35-60% - Very Gravelly >60% - Extremely Gravelly

10 Structure is the shape of a unit of soil as it is naturally bound together. These units, called peds, are like pieces of a puzzle that fit together. Structure is defined by type, grade, and size. Structure types are granular, blocky, platy, and prismatic. Grades are structureless, weak, moderate, and strong. Sizes are fine, medium, and coarse. Soil Structure

11 Soil Structure PRISMATIC STRUCTURE IN NJ SOILS GRANULAR SOILS

12 Wet Soil Consistence Soil consistence is the resistance of the soil structural unit to deformation at various moisture contents. Consistence may be a good indicator of liquid penetration. Typically, firm to very firm soil consistence results in slow permeability. Wet soil consistence terminology: Loose, Very Friable, Friable, Firm, Very Firm, Extremely Firm

13 Redoximorphic Features Soil mottling, which is a type of redoximorphic feature, is a soil characteristic associated with wetness. Mottling, or redox features, result from the reduction and oxidation of iron and manganese compounds in the soil. This splotchy appearance indicates intermittent saturation and desaturation. Redoximorphic features are described in terms of abundance and contrast, as well as size. Abundance: Few, Common, Many Contrast: Faint, Distinct, Prominent

14 Redoximorphic Features

15 USDA versus USCS

16 Unified Soil Classification System

19 Soil Forming Factors Climate primarily precipitation and temperature. Time the period of time since the parent materials became exposed to soil formation. Biota living organisms, especially native vegetation, microbes, soil animals, and human beings. Topography slope, aspect, and landscape position. Parent Material geologic or organic precursors to the soils.

20 Soil Forming Factors Classification of Parent Materials Formed in place from rock Residual Transported Colluvial by gravity Alluvial, Marine, Lacustrine by water Glacial by ice Eolian by wind (wind-blown loess) Accumulated plant debris Organic

21 Rock Depth Rock Depth 0-20 Shallow Moderately Deep >40 Deep, and Very Deep

Drainage Classification Drainage Classification <10 Poorly Drained 10-20 Somewhat

22 Drainage Classification Drainage Classification <10 Poorly Drained Somewhat Poorly Drained Moderately Well-drained >40 Well Drained, and Excessively Well Drained

23 Deep-Hole Soil Log

24 ASCE - Philadelphia Soil Water: Characteristics and Behavior Matthew C. Hostrander, CPSS, SEO Soil Scientist Gilmore & Associates, Inc.

25 Overview Soil water behavior Soil organic matter Perched water tables versus regional ground water tables Permeability testing methodologies

Soil Water Behavior Sandy soils will generally drain more vertically than horizontally; while soils high in clay will generally show drainage more

26 Soil Water Behavior Sandy soils will generally drain more vertically than horizontally; while soils high in clay will generally show drainage more uniformly in the horizontal and vertical directions. Water movement in stratified soils explained: Coarse soils over fine-grained soils and visa versa.

27 Soil Water Behavior Perched water tables can occur in some of the sandier soils around southeastern PA due to the following: Soil textural differences Structure Consistence Compaction Fill soil areas

28 Soil Organic Matter Soil Organic Matter Can increase infiltration rate Can increase water-holding capacity Can decrease erosion through aggregate stability Can increase nutrient removal through adsorption Can increase water retention over time Can provide macropores and channels for air and water Can increase food sources Overall, soil organic matter can help to keep irrigation and fertilizer use down, while providing less water pollution and greater groundwater recharge.

29 Soil Organic Matter

30 Water Tables

31 Water Tables Seasonally high water table due to poor draining soils and compaction

32 Prismatic soil structure is evident due to vertical redoximorphic features. A perched water table would existing above and within that horizon during wet parts of the year. Water Tables

33 Water Tables Redoximorphic features in a sandy soil can still occur. Also, the picture shows mobility of the surface sands into the sub-horizons through macropores.

34 Permeability Testing Methods Double-ring infiltrometer

35 Permeability Testing Methods Standard percolation test hole

36 Permeability Testing Methods Maryland falling-head cased borehole

37 Permeability Testing Methods Basin Flood testing, as modified from the New Jersey septic and stormwater regulations

38 Permeability Testing Methods Percolation testing allows horizontal and vertical water movement during the test. Double-ring infiltrometer testing mimics saturated vertical gravity flow with measurements taken from the inner ring.

39 Permeability Testing Methods Darcy s Law for calculating saturated hydraulic conductivity (ksat). Elrick & Reynolds equation for calculating the reduction factor, which accounts for the exfiltration occurring through the sides of percolation hole. It assumes that the percolation rate is affected by the depth of water in the hole and that the percolating surface of the hole is in uniform soil.

40 ASCE - Philadelphia Soil & Stormwater Engineering Matthew C. Hostrander, CPSS, SEO Soil Scientist Gilmore & Associates, Inc.

41 Why Stormwater Management? Groundwater Recharge Mechanism Erosion & Sediment Control (volume control) Safeguard Water Quality Waterway Protection

42 PA Best Management Practices Provides guidance for system selection, testing, analysis, construction, and maintenance. BUT The BMP Manual provides broad guidelines and should be expanded upon through testing and design. In practice, we have found that some sections need to provide more detailed guidance and information. Manual

43 START TO FINISH STORMWATER PROCESS 1. Desktop Review 2. In-situ Field Testing 3. Reporting / Recommendations 4. Stormwater Management Design 5. System Installation 6. System As-Builts 7. System Maintenance

44 DESKTOP REVIEW Review Site Soils County Soil Survey Web Soil Survey Soil Map Website Review Site Geology PA Geology Map Web Sources Review Municipal Regulations

45 DESKTOP REVIEW Possible Limitations 1. Seasonal High Water Table / Perched Water Table 2. Fine Grained Soils 3. Shallow Groundwater 4. Shallow Bedrock 5. Karst Geology 6. Wetlands

46 FIELD TESTING Soil Profile Descriptions Textural Class Limiting Zones 1. Seasonal High Water Table (indicated by ) 2. Bedrock 3. Groundwater

47 FIELD TESTING Infiltration Testing Methods Double-Ring Infiltrometer Standard Percolation Hole Basin Flood Maryland Borehole

48 FIELD TESTING Sealed cased borehole testing within existing athletic fields Confirmation double-ring infiltrometer testing during subsurface system installation

49 REPORTING & RECOMMENDATIONS Report Components Describe on-site soils and underlying geology Summarize infiltration rates and locations Discuss site limitations, if applicable Recommend appropriate stormwater management systems, if required

50 STORMWATER MANAGEMENT DESIGN Stormwater Management Systems Surface Systems Basins, Rain Gardens, Vegetated Swales, Berms, etc. Subsurface Systems Subsurface Infiltration Bed, Dry Wells, Infiltration Trenches, Constructed Filters Other Systems Permeable Paving with Infiltration Beds

51 STORMWATER MANAGEMENT DESIGN Goal To best match field conditions with a stormwater management design that responsibly promotes infiltration and mimics natural processes.

52 SYSTEM INSTALLATION Installation Challenges Compaction of the subgrade Construction practices Material selection Engineering (size, location, function)

53 SYSTEM MAINTENANCE Trim plantings Mow grasses Rehabilitation & Restoration (sediment) Observation port inspections (subsurface) Vacuum cleaning (permeable pavements only) Structural inspections

54 Q & A Stormwater Testing Stormwater BMP Design Regulatory BMP Manuals / Guidance Documents Consultant s Role Stormwater s Future

55 ASCE - Philadelphia Web Soil Survey: The Official Soil Survey Matthew C. Hostrander, CPSS, SEO Soil Scientist Gilmore & Associates, Inc.

56 Overview Web Soil Survey from the USDA Natural Resource Conservation Service Creating AOIs and Soil Reports Soil Data Explorer Soil Suitabilities, Properties, and Qualities Soil Map from PSU

57 Web Soil Survey Provides alternative to traditional hardcopy publication Provides means for quicker delivery of information Provides interactive access to most current data

58 Web Soil Survey Web Soil Survey allows the customer to get just the information they want or select The customer can obtain their geographic area of interest (AOI) information The customer can obtain relevant information to help answer their land use concerns (e.g. basements, crops, septic systems, etc.) Web Soil Suvey provides color imagery or topographic map backdrops for the AOI selected by the user Once the AOI is selected, a myriad of Soil Data Mart tables are available for viewing and use

59 Web Soil Survey Web Soil Survey can provide the user with a custom soil resource report (pdf format) via the free shopping cart The customized report can be prepared by AOI, soil map, map unit legend, map unit descriptions, etc. The user has the ability to customize the report with multiple soil data properties, capabilities, uses, and many others

60 Web Soil Survey Demonstration NRCS has 76 page WSS Tutorial available for use

61 Web Soil Survey WSS will generate a customized soil report for any project. The report, if small, can be printed directly from the website; however, for larger files, the report can be compiled externally and ed to you when complete.

IOWA FFA STATE SOILS CDE SATURDAY, OCTOBER 13, 2007 AMES, IOWA

IOWA FFA STATE SOILS CDE SATURDAY, OCTOBER 13, 2007 AMES, IOWA 1. Moderately sloping has what percent slope: a. 9-14% b. 2-5% c. 5-9% d. over 14% 2. Which of the following horizons is the loose underlying