implementers february 2013 our islands our future guide to green building in the usvi funded by...

IMPLEMENTERS

February 2013

Our IslandsOur Future

GUIDE TO GREEN BUILDING in the USVI

Funded by NOAA’s Coral Reef Conservation Program through NOAA Fisheries Caribbean Field Office

Developed by The FHWGroup and reviewed by a steering committee of federal and VI agencies and NGOs

Guide to Green Building in the VI Introduction

Introduction

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As a heavy equipment operator or contractor, you play a crucial role in the construction of buildings and the preservation of the environment that surrounds those buildings.

With growing problems of water quality that affect the health of our marine environment, going “green” is a necessity. The information that follows will assist you in preparing sites for your clients in a way that will protect our natural resources and preserve the natural beauty of our islands.

Elevated Double Pedestal House, St. Thomas

Panoramic View of Cruz Bay, St. John

Photo Credit: http://blog.topsider.com/category/home-building-virgin-islands


Introduction

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Your work is your signature and your signature will get you your next job. Your signature will remain on the site forever, so work smart and sign small!

We will show you how to work green before, during, and after site preparation, construction, and final grading and landscaping.

LESSON 1

Work Green Site Preparation

LESSON 2

Work Green Construction

LESSON 3

Work Green Project

Completion

**Click picture to go directly to the lesson of interest


Introduction

The lessons contained in this module may be used as a part of an instructor-led course on green design and construction or used directly by construction industry professionals. You can review the lessons in any order based on your interest and expertise.

Development industry professionals completing the full training, including the field component, will be acknowledged publicly and may receive assistance from Island Green Building Association (IGBA).

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Introduction

The lessons that follow will:1. Provide information on

minimizing disturbance to natural resources during site preparation.

2. Provide guidance for installation and maintaining best management practices during construction.

3. Provide guidance for concluding site work, including final grading, landscaping, and maintenance.

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Photo Credit: ESA Solar – St. John Installation

Rooftop Solar Panel Installation

Intro

Lesson 1

Lesson 2

Lesson 3

GOALProvide a basic

understanding of how to protect natural resources beginning with

site preparation

LEARNING OBJECTIVES Identify some natural resources that

are protected in VI Identify the steps in initial site

preparation and ways to work “green” to protect our natural resources

1Work Green -

SITE PREPARATION

Guide to Green Building in the VI Lesson 1 – Site Preparation

Work Green – Protect VI’s Natural Resources

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The VI’s natural resources, such as native vegetation, water courses, and marine habitats, are afforded protections under existing Territorial and Federal regulations like the Coastal Zone Management Program and the Clean Water Act.

Other resources, such as the VI boa, St. Croix ground lizard, sea turtles, elkhorn and staghorn corals, and plants like mangroves, have additional special protections.

Photo Credit: http://www.stcroixhotelandtourism.com/ecotourism.php

St. Croix ground lizard

Photo Credit: http://soundwaves.usgs.gov/2010/04/

Photo Credit: http://www.earthsendangered.com/profile.asp?ID=9&sp=557

VI tree boa red mangroves


Work Green – Protect VI’s Natural Resources

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In the project design phase, surveys of the site should have been conducted to determine what natural resources occur on the site. Areas to be protected on site should also be marked on the plans. Resource protection also includes installation and maintenance of all required BMPs for erosion, sediment, and runoff control and management.

Be sure you are aware of what threatened or endangered plants and animals look like and the steps you should take if you see them while working on site. Fines and even jail time are possible if you cause harm to these resources, so be sure to follow all permit special conditions to follow to protect these resources and to contact the resources agencies and your project team if in doubt.


Work Green – Before Any Earth Movement

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1. Ensure approved, stamped permits are on site.

2. Contractor does a walk-through with HEO to review the marked-off footprint of the area to be disturbed AND to identify marked trees, setbacks, and other features where no disturbance should occur.

3. Ensure perimeter controls such as silt fencing are installed.

4. Study project plans to familiarize yourself with project phasing and map out what and where temporary and permanent stormwater and erosion and sediment controls are required on site.

5. Ensure you have the contractor’s contact number for questions that may arise as you grade the site

Strategies you should use to protect the natural resources on a site:

jlhare.com/about-j-l-hare-associates/



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1. Ensure approved, stamped permits are onsite.






Group discusses erosion control strategy for site in the Fish Bay Watershed.

Photo Credit: Island Resources Foundation.



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3. Ensure silt fences are properly installed around the perimeter of the site.




Multiple lines of silt fences and use of cut brush to help control erosion.Photo Credit: Island Green Building Association



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Figure: http://cfpub.epa.gov/npdes/stormwater/menuofbmps/index.cfm?action=browse&Rbutton=detail&bmp=116&minmeasure=4



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5. Ensure you have contact numbers for the contractor, architect, and others on the project team who can answer any questions that may arise as you begin earth movement on the site.


Photo credit: Horsley Witten Group http://www.horsleywitten.com/



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Before beginning any earth change work on site, remember to check:

1. Project plans to be sure the physical characteristics of the site (soils, topography, hydrology, and vegetation) match the proposed best management practices (BMPs) for sediment and erosion control and management of runoff

2. 150 foot buffer or setbacks adjacent to shorelines, 25 foot buffers adjacent to ghuts or 30 feet from ghut centerline, whichever is greater, and 50-150 foot setbacks from ponds and wetlands are clearly marked on site

3. All trees and other vegetation to be preserved on site are clearly marked

4. The disturbance footprint for all construction activities is clearly marked on site

Goal is to prevent any runoff or sediment transport off site.


Initial Steps in Site Preparation

Hand clear trails and small areas only using non-mechanical equipment

No mechanical clearing or machine clearing of any kind is allowed before a CZM permit and any required Federal permits for mechanical clearing and other site work (if area contains wetlands, ghuts, or other water bodies or is along the shoreline) are received

Preserve all trees at this time

Build sturdy fences, wood, or steel barriers around all vegetation to be protected from construction and construction equipment. Barriers should be placed such that tall equipment doesn’t injure branches. Roots should also be protected from excavation.

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Site Preparation

All site preparation must create minimum erosion, runoff, and sediment transport off site

All site preparation must minimize impacts to natural resources

A way to accomplish both of these goals is to clear vegetation ONLY in immediate area around the building footprint and to clear vegetation only when construction will begin as soon as the area is cleared.

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Key Points

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1. All of VI’s natural resources should be protected and are afforded legal protections under Territorial and Federal regulations. However, there are some plants and animals (terrestrial and marine) that are afforded additional protections. You should be aware of whether or not these are found on your site and of any permit special conditions to protect these resources to avoid fines and other penalties.

2. It is important to work green before any earth change occurs by ensuring• stamped, approved, final copies of all permits and plans are

readily available on site• you do a walk through and review the marked disturbance

footprint and any areas and vegetation to be protected• Silt fences are in place around the perimeter• Familiarity with project phasing and all required temporary

and permanent BMPs

3. There are some important initial steps in site preparation that need to be followed to protect vegetation and other resources and ensure all stormwater and sediment is properly contained on site.

Guide to Green Building in the VI Lesson 1 – Site Preparation 18

Before Grading NotesYou have all required approved, stamped permits on site prior to beginning any mechanized work.

☐ ☐YES NO

You know what natural features need to be protected. You can identify protected plants and animals and know what to do if you see them on site during construction.

☐ ☐YES NO

You ensure the footprint of the area to be disturbed is clearly marked on site. Heavy equipment operators have done a walk-through to view limits of site disturbance and areas and vegetation to be preserved.

☐ ☐YES NO

You ensure silt fencing is correctly installed along perimeter. ☐ ☐

YES NOYou have built temporary barriers around all vegetation to be preserved on the site. ☐ ☐

YES NO

WORKING GREEN Site Preparation CHECKLIST

Guide to Green Building in the VI Lesson 1 – Site Preparation 19

Before Grading NotesYou have studied project plans and the physical characteristics of the site and made modifications to the best management practices (BMPs) to be used as necessary based on slopes and soils.

☐ ☐YES NO

You have studied project plans and are familiar with project phasing and the locations of temporary and permanent BMPs for sediment and erosion control and stormwater management.

☐ ☐YES NO

You have installed all required BMPs based on the project phasing prior to commencing any mechanized work.

☐ ☐YES NO

You have the project team’s contact numbers readily available for questions that may arise as you begin grading the site.

☐ ☐YES NO

WORKING GREEN Site Preparation CHECKLIST

Intro

Lesson 1

Lesson 2

Lesson 3

GOALProvide practical

strategies for protecting natural resources during earth change

and construction

LEARNING OBJECTIVES Describe the importance of BMPs

and what they do Identify different types of temporary

and permanent BMPs’ Identify how to properly install some

commonly used BMPs Identify maintenance requirements of

different types of BMPs

2Work Green - CONSTRUCTION

Guide to Green Building in the VI Lesson 2 - Green Construction

What is Erosion?

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Erosion is the detachment of a portion of the soil profile or soil surface. This can occur by either the impact of raindrops, or by the shear forces of water flowing across the soil surface.

road covered with eroded sediment

eroding slopePhoto Credit: Sharon Coldren - The Coral Bay Watershed Management Project: Being a Partner and Building Partnerships.


Erosion Control Practices

Best Management Practices (BMPs) for erosion control hold soil in place and reduce the potential for soil to be removed by stormwater (mulching, riprap, seeding sodding, surface roughening).

The most effective erosion control practices are to preserve the existing vegetation and to replant cleared or bare areas quickly.

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What is Sediment?

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Eroded or exposed soil particles (sediment) can be transported by rainwater and deposited short or long distances downslope of their point of origin. The transport and deposition process is called sedimentation. Typical Forces in Soil Erosion

Figure: http://onlinemanuals.txdot.gov/txdotmanuals/hyd/soil_erosion_control_considerations.htm


Sediment Control Practices

BMPs for sediment control remove eroded soils from runoff before it leaves the property. These measures are not as effective as erosion control because most soils in the Virgin Islands are clay and most BMPs cannot remove clay from runoff.

It is much easier and more cost effective to keep soil in place than to attempt to remove it from stormwater.

Permanent sediment control practices are used to convey stormwater runoff to safe outlets away from erodible areas and/or treat stormwater runoff to remove sediment (brush berms, compost socks, silt fences, storm drain inlet protection, sediment traps, sediment basins). These practices need to be maintained over the project lifetime.

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What is Runoff?

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Surface runoff occurs when the soil is infiltrated to full capacity and excess water from rain or other sources flows over the land.

To reduce the potential for runoff and erosion, land clearing and earth change activities should NOT be planned during the rainy season.

road flooded with surface runoffPhoto Credit: Sharon Coldren - The Coral Bay Watershed Management Project: Being a Partner and Building Partnerships.


Runoff Control Practices

BMPs for runoff control maintain water on-site. Both conventional, structural stormwater controls and low impact development (LID) measures may be used to control runoff.

LID principles are based on controlling stormwater at the source by the use of controls that are distributed throughout the site (rain gardens, grass swales and channels, vegetated rooftops, rain barrels, cisterns, vegetated filter strips, and permeable pavement). This is unlike conventional approaches that typically convey and manage runoff in large facilities located at the base of drainage areas (check dams, grass-lined channels, permanent slope diversions, temporary diversion dikes).

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Low Impact Development Ideas

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Minimum driveway reduces runoff

Rain Garden keeps runoff on site

reinforced grass swale directs runoff

Your cistern collects rainwater and reduces water running off the site

Horsley Witten Group

www.tensar.co.uk/www.igbavi.org/

Photo Credit:Hosana Solomon


Low Impact Development Ideas

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This is an example of the use of a gravel construction entrance at a residential construction site in Mt. Washington, St. Croix. The placement of gravel is temporary in order to prevent exposed dirt from eroding.



Work Green – During Rainy Season

Think about the rainy season as “Give Your Machine a Brake” season. Take the opportunity to travel, relax, and rest during hurricane season (August to November).

Keep yourself and your machinery safe by staying off unsafe slopes during heavy rains. Take the opportunity to get maintenance done to your equipment during this time and help us protect our natural resources from the impacts of sediment-laden runoff

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Photo Credit: Sharon Coldren - The Coral Bay Watershed Management Project: Being a Partner and Building Partnerships.


BMP Selection Strategy

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On any construction site, the objective of erosion and sediment control and runoff management is to prevent off-site transport of sediment and runoff.

BEFORE beginning earth change operations, be sure all required temporary and permanent erosion, sediment, and runoff BMPs have been installed.Typical uses and locations for erosion prevention and sediment control BMPs. (Source: Idaho Construction Site Erosion and Sediment Control Field Guide)


Work Green – Beginning Earth Change

Once the project has all the required permits and they are posted on-site along with final, stamped plans, you are ready to begin the process of clearing the areas to be disturbed.

Plan ahead – AVOID excavation and other work that exposes bare soils during the rainy season. Sediment loading to nearshore waters, including coral reefs, has been shown to increase dramatically if work is done during wet periods because BMPs are not as effective due to the amount of runoff generated and the fact that work often has to stop during bad weather, leaving soils exposed.

The first step is to create berms and swales to contain runoff from cleared areas. Then you need to ensure all environmental protection measures are installed BEFORE beginning any mechanical site work.

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Work Green – Beginning Earth Change

As part of BMP installation, be sure to note the location of all existing storm drains on the site and create temporary diversions of these PRIOR to beginning any mechanical clearing

Diversions can be: a sediment trap below a permanent outfall an in-line diversion of an inlet or a manhole the installation of a retention basin early in the

construction sequence the delay of the completion of a permanent

outfall and the temporary diversion of runoff to a sediment trap

Additional inlet protections are not needed if diversions have been installed and are functioning properly 32


Work Green – During Earth Change

Use smaller heavy equipment and minimize number and size of cuts on hillsides.

Erosion control measures must be installed as quickly as possible where construction has temporarily or permanently stopped for more than 14 days.

No excavation for footings, foundations, cisterns, wastewater treatment, etc. should be done if construction work will not begin within 14 days so as not to expose bare soils to rain and wind.

Use serrated cut slopes in areas where cuts will be steeper than 50% behind buildings and next to driveways and roads.

Use benches to break long (more than 20 to 40 foot) slopes and route runoff to a sediment trap or stabilized outlet.

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Work Green – During Earth Change

Make sure no grading impairs existing surface drainage, constitutes a potential erosion hazard, or acts as a source of sediment to ghuts. Respect all buffers, green belts, and setbacks and protect all native stream fauna, shorelines, and wetlands. Do not allow equipment, vehicles, or construction materials to cross or be stored in setbacks, buffers, or green belts.

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Work Green – Protect Vegetation

Start tunnels under root systems for underground utilities at least 18 inches below the ground surface.

Don’t pile more than 3 inches of soil over trees and shrub roots.

Use retaining walls or terraces to protect roots when lowering grades. Begin lowered grades outside tree drip-line. Don’t trench across roots within the drip-line (or trees could be weakened to the point of collapse).

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Soil Stabilization During Earth Change

Stockpile and temporarily seed or cover topsoil with tarps or erosion control mats. Ensure all stockpile and borrow areas are shown on project plans.

When larger areas are to be cleared, run heavy equipment up and down slope to create grooves perpendicular to slope. This will channel runoff across slope instead of down to reduce erosion from gullying.

Compact all fills to reduce erosion, slippage, settlement, and subsidence.

Keep fill material free of brush, rubbish, rocks, logs, stumps, and building debris.

Provide adequate drainage for seeps and springs so excess water doesn’t lead to slope failure.

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More on Soil Stabilization

Chemical sealers/binders are used to minimize dust and erosion from dirt roads, on very steep slopes or very dry soils, or on other areas where it is difficult to establish vegetation.

If using chemical sealers/binders, make sure they are environmentally safe

Mulch is also used to stabilize exposed soils. Examples of mulch are straw or hay, wood fiber (jute), mulch netting, crushed stone, or wood chips.Vegetated filter strips are another soil stabilization measure. Hydroseeding may be used to create these filter strips.

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Save Brush & Boulders

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Berms are placed to reduce the transport of coarse sediment from a construction site by providing a temporary physical barrier to sediment and reducing the runoff velocities of overland flow. These barriers are intended for use with small drainage areas up to one-quarter acre per 100 lineal feet of berm. They should not be used in high volume, high velocity flows.

Use brush from the site to make berms! (And save boulders for use in retaining walls, check dams, or other rock structures.)The vegetated part of branches should be placed in contact with the ground. Limbs should be layered to form a berm. Berm should be constructed in lifts with each layer extending the length of the berm prior to the next layer placement.

Figure: http://sddot.com/business/design/docs/wqep/Data_Sheets/BrushBerm.pdf

A brush berm is a barrier that consists of woody brush and branches less than 2 inches wrapped in filter fabric and anchored to the ground.


Brush Berm & Silt Fence Design Detail

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Brush berms are regularly installed with silt fences on construction sites in the USVI. In the example on the right, cleared vegetation on a site in Coral Bay is used to construct a brush berm (18 inches high) that is designed to be installed 24 inches in front of a filter fabric fence (silt fence).

Figure: NOAA ARRA USVI Watershed Stabilization Project, Carolina Valley, St. John


Erosion Control Blanket Installation

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1. Grade, disk, and prepare seedbed. Seed the area before blanket installation. For long slopes, install blankets up and down the slope face. For channels, install blankets parallel to flow of the channel, as per manufacturer’s directions.

2. Install the product starting from the top of the slope, anchored in a 6” x 6” trench that is backfilled and tamped firmly. Anchors/staples are “U” shaped and a minimum of 6 inches long. Longer staples are used in sandy soils.

Figure Credit: Idaho Construction Site Erosion and Sediment Control Field Guide


Erosion Control Blanket Installation

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3. Walk blankets down slope to ensure good contact with the soil. Staple blankets every 12 inches on tops and 18 to 36 inches down the sides and in the middle or according to manufacturer’s directions, whichever is more protective.

4. Do not stretch blankets.

5. Do not exceed manufacturer’s directions on maximum slope angle for the product.

6. Additional staking or stapling is needed for applications in channels that carry flowing water and on steep slopes. Inspect before and after each rain event and twice monthly until the tributary drainage area has been stabilized.

Figure Credit: Idaho Construction Site Erosion and Sediment Control Field Guide


Sediment Control – Silt Fence

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A silt fence is a temporary linear barrier that captures sediment by ponding stormwater runoff, allowing sediment to settle out.

A silt fence can be used along slopes, below exposed soil areas, and around temporary stockpiles. In general, each 100-foot section of silt fence treats runoff from approximately 1/4 acre (about 100 feet uphill). The runoff contained by each silt fence shouldn’t be from more than one acre. On slopes greater than 25%, install reinforced silt fences in rows 10-15 feet apart.

Figure: Idaho Construction Site Erosion and Sediment Control Field Guide


Silt Fence Installation

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1. Note the location and extent of the bare soil area. Mark silt fence location just below bare soil area. Make sure fence will catch all flows from area.

2. Dig trench a minimum of 6 inches wide and deep across slope.

3. Unroll silt fence along trench. Push geotextile into trench; spread along bottom and sides.

4. Drive posts on downhill side a maximum of 6 feet apart.

5. Secure silt fence to posts with staples, wire, or as recommended by manufacturer. If needed, join fencing by rolling the end posts together. Steel posts are the most effective because they will not be damaged by insects or rot. Reinforce fences with steel posts and wire mesh backing for steeper slopes.

6. Do not place joined sections in low spots or sump locations. Fill trench with soil and tamp down.



Silt Fence Installation

44

Properly Installed Silt Fence Improperly Installed Silt Fence

This silt fence is correctly installed. The steel posts are installed on the downhill side. A wire mesh backing has been added for this steeper slope to prevent undercutting.

Reminder: A silt fence is a temporary linear barrier and is not designed to withstand high heads of water. A silt fence should NEVER be installed across drainage ways, ghuts, or channels.

This silt fence is incorrectly installed. The posts are installed on the uphill side of

the fence. The bottom of the fence also appears loose in several areas.

Adequate trenching and backfill is needed to ensure bottom of fence stays

in place.

Photo Credit: Idaho Construction Site Erosion and Sediment Control Field Guide


Sediment Control – Compost Sock

45

Compost socks can be used as an alternative to silt fencing and also work well to protect storm drain inlets.

They function by intercepting runoff, reducing runoff flow velocity, ponding runoff, allowing sediment to settle out, and releasing the runoff as sheet flow. Compost socks cannot be used on slopes greater than 2:1. Compost socks can be created using materials from site clearing.



Compost Sock Installation

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1. Install along contours starting at the toe of the slope, or slightly away from the toe, and every 3 to 30 feet along the slope depending on the steepness of the slope, soil type, and rainfall. The steeper the slope the closer together the compost socks should be.

2. Compost socks shall not be used on slopes greater than 2H:1V.

3. Use only cured or finished compost.

4. Compost socks shall be filled so they are firmly packed yet flexible. Once placed on the ground, apply temporary weight to the sock to improve contact with the underlying surface. This may cause the sock to assume an oval shape.



Compost Sock Installation

47

5. Install stakes at each end of a compost sock, and at 3-foot centers along the entire length. If required, install pilot holes through the compost sock and into the soil prior to installing stakes. Stakes should be installed perpendicular to the ground surface and on a slight angle alternating left to right. The stakes at angle prevent the sock from lifting or floating during the first rain event.

6. Wooden stakes should be 2” x 2” x 36” minimum. Cut branches or 3/4 inch rebar can also be used as stakes.

7. If more than one compost sock is installed in a row, tightly abut end to end the two adjoining socks.

8. Turn ends of compost socks uphill to prevent water from flowing around the barrier.



Protecting Storm Drains & Other Inlets

48

Muddy runoff that flows toward a culvert, ditch, or storm drain inlet must be slowed down and pooled or filtered to settle out and remove sediment. This can be accomplished by excavating, placing rock, reinforced silt fencing, silt dikes, stone or blocks, or other barriers or curb drops in front of the inlet.

All of these choices can handle runoff from a 1-acre drainage area maximum.

The goal is to cause ponding so sediment can settle out before ponded water enters the inlet.

Photo Credit: http://www.ars.usda.gov/is/pr/2010/100723.htm

Filter socks containing compost tucked into mesh tubes are used to keep some of the silt, heavy metals, fertilizers, and petroleum products washed from compacted surface areas from going into nearby waterways.


Protecting Inlets

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The inlet shown above is not properly protected. The geotextile does a poor job of helping to slow and pool runoff. The material is also difficult to remove when filled with sediment.

The inlet shown above is adequately protected. Gravel

bags will help to slow and pool runoff. Accumulated sediment can

be easily removed.


Protecting Outlets

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Outlet protection prevents scour and erosion at outlets by reducing the depth, speed, and energy of concentrated stormwater flows. Outlet protection should be installed at the outlets of culverts, ditches, storm drains, piped slope drains, and any channels that discharge into natural waterways or constructed channels.

Outlet protection can be stone, rip rap, grouted rip rap, or gabions.

Outlet protection is made by placing rip-rap, which is large, angular rock, at the outlet of conveyance channels, sediment traps, or pipes. This practice slows down and spreads water out, thereby preventing erosion at the point of discharge.

Photo Credit: http://www.aiswcd.org/IUM/standards/urbst910.html


Sediment Control – Temporary Sediment Basin

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• A settling pond with a controlled stormwater release outlet is used to collect and store sediment produced by construction activities.

• Sediment storage volume must be at least 3,600 cubic feet per acre of disturbed area draining to basin.

• Built by excavation and/or by placing an earthen embankment across low areas, drainage channels, or swales.

• Can be designed to maintain a permanent pool or to drain completely dry. They are used for drainage areas of 10-20 acres.

Figure: http://www.cep.unep.org/pubs/Techreports/tr32en/content.html

Small sediment basin with outlet pipe discharging on riprap to prevent erosion at discharge end


Sediment Control – Temporary Sediment Basin

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Installation of a sediment trap at Whispering Hills Affordable Housing Construction Site, St. Thomas East End.Photo credit: Frank Galdo


Work Green - Driveways

All driveways should be surfaced with pavement or permeable pavers after grading is complete. Gravel should not be used to permanently pave areas, especially where there are steep slopes. Gravel driveways on steep slopes contribute to erosion and gullying by stormwater, although their contribution is less than that of unpaved roads.

Exposed earth driveways or driveway cuts should not remain unstabilized for more than 30 days after their creation. Soil stabilization (mattings, temporary seeding, etc.) is required during and after construction

A silt fence, even if properly installed, is not enough to manage erosion and stormwater runoff from unpaved driveways

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Work Green – Construction Entrances

A stabilized construction entrance should be installed at every entrance/exit to prevent soil from being tracked or washed off site to public roadways.Guidelines: Minimum 30 foot length for single residential lot, 50 foot for

other sites 10 to 12 foot minimum width flare at existing road for

turning Filter fabric placed over existing ground surface prior to

placing stone (although may not be necessary for individual home site)

Place 2 – 3 inches of crushed aggregate at least 6 inches deep over length and width of entrance

Pipe all surface water flowing to or diverted toward construction entrances and protect pipe with a berm. Size pipe according to drainage area with minimum 6 inch diameter or use a 5:1 slope berm if piping is impractical

Regularly maintain54


BMP Maintenance

In order for BMPs to be effective, they must be maintained during construction and during the project lifetime if the BMPs are permanent. The following are maintenance practices that need to be followed for different BMPs: Filter strips – maintain edges to prevent the formation of

concentrated flows, mow, do spot repairs of vegetation Temporary seeding/hydroseeding – complete spot repairs by

reseeding/mulching, mow grass swales and embankments Sediment traps – remove sediment when accumulation is to

½ of design depth, repair embankments and rock filters Temporary sediment basins – repair damage from soil

erosion and construction equipment at or before end of each work day, clean basins when they are at 50% fill by volume or when sediment is within 1 inch of bottom of the principal spillway crest

Silt fences – replace any failed stakes, clear accumulated sediments behind fences, replace hay bales that have been placed upslope of fences regularly

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BMP Maintenance – Sediment Disposal

For all BMP maintenance related to sediment control, be sure all accumulated sediment that is removed from traps, settling basins, etc. is disposed of properly.

NEVER dispose of sediments downstream from an embankment (natural or part of a BMP), adjacent to a drainageway, or in a floodplain.

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Key Points

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1. BMPs are used to manage erosion, sediment, and runoff. The most effective measure is to minimize site disturbance and phase earth change work so that exposed soils can be stabilized quickly.

2. BMPs can be temporary or permanent. All measures need to be in place before earth change begins.

3. Ensure silt fences, erosion control blankets, and other BMPs are properly installed to ensure all sediment from your project is retained on site and runoff off site is minimized. Make sure you have included construction entrance/exit sediment controls.

4. BMPs require regular maintenance to be effective. Be sure sediment that is cleaned from sediment control BMPs is properly disposed of and that BMP maintenance is part of your regular work schedule on site.

Guide to Green Building in the VI Lesson 2 - Green Construction 58

During Construction NotesYou have planned required excavation and other earth movement work that results in exposed soils for completion outside the rainy season.

☐ ☐YES NO

You have ensured that all sediment and erosion control and stormwater BMPs are properly installed BEFORE beginning any mechanized work on-site. This includes stabilized construction entrances.

☐ ☐YES NO

You have created berms and swales to contain runoff from cleared areas as you begin site clearing and grading. Brush from the site can be used to create berms and boulders can be used for more permanent structures such as retaining walls.

☐ ☐YES NO

You have installed temporary diversions of existing storm drains BEFORE beginning any site clearing.

☐ ☐YES NO

WORKING GREEN Construction CHECKLIST


During Construction NotesYou ensure no excavation work will begin if soils will be exposed for 14 days or more. ☐ ☐

YES NO

If there is a construction stoppage that has already lasted 14 days, you install erosion control measures IMMEDIATELY to minimize erosion of exposed soil.

☐ ☐YES NO

You create serrated cut slopes if cuts are steeper than 50% behind buildings and next to driveways and roads.

☐ ☐YES NO

You construct benches to break slopes of more than 20 to 40 feet and route runoff to a sediment trap or stabilized outlet to minimize sediment and runoff transport offsite.

☐ ☐YES NO

You do not cross or store equipment, vehicles, or construction materials in setbacks, buffers, or green belts.

☐ ☐YES NO



During Construction NotesYou protect vegetation by tunneling under roots to install utilities, avoiding piling excess soil on and around roots, and building retaining walls or terraces.

☐ ☐YES NO

You ensure that all soil stockpiles are covered to prevent erosion of material during rains.

☐ ☐YES NO

When large areas need to be cleared, you run heavy equipment up and down slope to create grooves and channel runoff across the slope to minimize gully formation.

☐ ☐YES NO

You compact all fill material and use fill that is free of vegetative and construction debris to ensure it can be well compacted.

☐ ☐YES NO

You ensure all BMPs are properly maintained as part of daily construction activities and a regular maintenance schedule.

☐ ☐YES NO


Intro

Lesson 1

Lesson 2

Lesson 3

GOALProvide practical

strategies for protecting natural resources at the conclusion of

the project

LEARNING OBJECTIVE Describe process of final site

stabilization and landscaping Describe BMP maintenance

requirements and process for removal of temporary BMPs

3Work Green -

PROJECT COMPLETION

Guide to Green Building in the VI Lesson 3 – Project Completion

Work Green – Final Site Stabilization

Once construction is complete, your site needs to be permanently stabilized and landscaped following the project plans.

Complete all permanent seeding and planting, final retaining walls on cut or steep slopes that cannot be planted (use boulders from site clearing in walls). Install porous pavers to reduce erosion and stormwater runoff and rain gardens (also called bioretention ponds) to help absorb rainwater on site. 62

Photo Credit: Island Green Building Association

Rain Garden in Hope & Carton neighborhood, St.

CroixPhoto Credit: Michelle West, Horsley Witten Group

Minimum driveway reduces runoff


Remove Temporary BMPs

Temporary sediment basins - should be removed at the end of their lifetime once construction is complete as part of final site grading and after the drainage area has been stabilized. Level embankments and properly dispose of sediments at approved upland site. 63

Sediment traps – regrade and plant areas where temporary sediment traps were installed after all construction is complete and as part of the restoration of stormwater drainages.

Temporary sediment trap at Cocoloba Trail

Temporary sediment trap at John Head Road

Photo Credit: Island Resources Foundation. Erosion Control Strategy for the Fish Bay Waters.


Remove Storm Drain Diversions

Once areas contributing sediment have been stabilized, the permanent storm drainage system should be restored.

Remove all accumulated sediment. Establish permanent, stabilized outfall channel based on project plans.

Where inlet was modified, plug temporary pipe stub and open the permanent outfall pipe

Remove temporary sediment control devices for traps that will be converted to stormwater management

64


Maintenance Requirements

Seed/Sod – repair bare spots by reseeding and/or mulching, mow grass frequently to control weeds (at least 2 inches above ground during wet season and longer during dry season)

65

Rain garden/bioretention ponds – inspect monthly until plants establish then inspect annually, replant as needed, remove sediment from behind check dams when accumulations reach ½ dam depth

runoff control maintenance

Volunteers help clean out a clogged runoff drainage structure in Fish Bay

Photo Credit: Island Resources Foundation. Erosion Control Strategy for the Fish Bay Watershed.


Maintenance Requirements

66

This is a stormwater retention basin in Kingshill Road, Coral Bay, St. John. Sediment needs to be removed or else erosion control function of the basin is lost.

Evident sediment build up in retention pond located along Kingshill Road, Coral Bay, St. John. Removal of excess sediment is important to maintain proper function of the pond.



Key Points

67

1. As part of the completion of construction on your site, finalize all grading, slope and cut stabilization, and landscaping

2. Remove temporary BMPs and provide maintenance to permanent BMPs

3. Restore and complete stormwater drainage system according to site plans for your project

Guide to Green Building in the VI Lesson 3 – Project Completion 68

After Construction Notes

You complete final site stabilization, including all permanent seeding and planting and the construction of final retaining walls on cut or steep slopes, as part of final site grading.

☐ ☐YES NO

You remove all temporary BMPs and properly dispose of all accumulated sediments on uplands away from ghuts and other wetlands and water bodies.

☐ ☐YES NO

You restore the permanent stormwater drainage system, including the removal of all storm drain diversions.

☐ ☐YES NO

You have ensured the site owner is aware of the maintenance requirements for permanent BMPs and have assisted in creating a maintenance schedule for the property if one was not included as part of project design.

☐ ☐YES NO

WORKING GREEN Project Completion CHECKLIST


Learn More

69

BMPs for Stormwater Management

Photo Credit: Michelle West, Horsley Witten Group

Constructing a Native Soil Rain Garden http://www.caes.uga.edu/extension/water/lc/documents/ConstructingaNativeSoilRainGarden.pdf

National Menu of Stormwater Best Management Practiceshttp://cfpub.epa.gov/npdes/stormwater/menuofbmps/

BMPs for Sediment & Erosion Control

Sediment & Erosion Control on Construction Sites http://www.coralreef.gov/transportation/sederosuvi.pdf

Virgin Islands Environmental Protection Handbook. 2002. http://dloc.com/CA01300680/00001

LEED for Contractors, Construction Activity Pollution Preventionhttp://www.leedforcontractors.com/filling-out-the-leed-online-scorecard/construction-activity-pollution-prevention

US Green Building Council http://usgbccaribbean.org/

Rain Garden in Hope & Carton neighborhood, St.

Croix

http://www.caes.uga.edu/extension/water/lc/documents/ConstructingaNativeSoilRainGarden.pdf



http://cfpub.epa.gov/npdes/stormwater/menuofbmps/



http://www.coralreef.gov/transportation/sederosuvi.pdf



http://dloc.com/CA01300680/00001

http://dloc.com/CA01300680/00001

http://www.leedforcontractors.com/filling-out-the-leed-online-scorecard/construction-activity-pollution-prevention




http://usgbccaribbean.org/

Guide to Green Building in the VI Acknowledgements

Acknowledgements

70

Steering Committee

Department of Planning & Natural Resources Alex Holecek, Program Analyst - Division of Coastal Zone ManagementJean-Pierre Oriol, Director – Division of Coastal Zone ManagementRoy A. Pemberton Jr, Director Division of Fish and WildlifePhillip Smith, Director - Division of Building Permits

Island Green Building AssociationBarry DevineKaren VahlingWilliam Willigerod

NOAA's Coral Reef Conservation Program, OCRMMarlon Hibbert, USVI Management Liaison

NOAA FisheriesLisamarie Carrubba, Protected Resources DivisionLia Ortiz, Coral Reef Conservation Program USVI Fishery LiaisonGlenis Padilla, Coral Reef Conservation Program Biologist

US Army Corps of EngineersEdgar Garcia

U.S. Fish and Wildlife ServiceFelix Lopez

Green Building Council, Caribbean ChapterBrenda Martinez

OthersHorsley-Witten Group, Sharon Coldren and Coral Bay Community Council, Island Green Building Association,

Photo Credits The photos used on the cover slide and section introductions were obtained from the following sources: www.dpnr.gov.viwww.solarsystemsvi.com

implementers february 2013 our islands our future guide to green building in the usvi funded by...

Documents

site preparation work

work green construction

green design

work green project completion

concluding site work

vis natural resources

initial site preparation

intro lesson