Enough soil can erode from a typical construction to pollute three miles of downstream waters for a century. However, with the use of the right protection measures this pollution can be dramatically reduced. THE most effective measure is to prevent erosion by covering exposed soil with straw mulch, grass, or other "stabilization" methods. Other measures, like the black silt fence pictured to the right, simply can't keep enough mud on the site to prevent pollution.
In fact, whenever you see exposed soil on a construction site, pollution will occur come the next rain.
There are two ways you can help bring construction site mud pollution to an end:
Click this image to view a six-minute YouTube introduction to how you can help halt construction site mud pollution.
Because of the tremendous benefits, all Chesapeake Bay watershed states and the District of Columbia requires protection of all disturbed soils within 3 to 30 days following the start of construction. However, compliance with this vitally important law is less then 100% in many parts of the Bay watershed. Until we can improve compliance, efforts to restore the Chesapeake Bay and our many other degraded waterways will be in jeopardy. This is where you come in and how you can save a hundred feet of waterway with just a few minutes to an hour of your time by either signing our petition or reporting sites with exposed soil.
The answer to this question is simple: Clay. Soil is made up of three particle sizes: sand, silt and clay. Clay is the smallest and the hardest to remove once it has been eroded from the soil surface and entrained in runoff. Sand and silt can be kept on a construction site by silt fence, sediment traps (like that pictured here), and other measures. These measures mostly rely upon settling to remove sediment from runoff. These larger particles settle fairly quickly while days or weeks may be required for clay to settle from suspension. So, the most effective way of keeping clay on a construction site is to prevent erosion, which means minimizing the exposure of soil to the erosive force of rainfall and runoff. This, in turn, means protecting soil as quickly as possible following disturbance with a layer of mulch, then grass, or other stabilization measures.
One might think that the small size renders clay particles harmless. In some respects the opposite is true. Much of the phosphorus, pesticides, and other pollutants washing from construction sites travel attached to clay particles. Many fish eggs have a slightly sticky coating and clay can adhere so thickly that the developing embryo suffocates. Clay is the most expensive particle to remove from drinking water sources. Clay and other suspended particles are responsible for a large portion of the turbidity which blocks sunlight and has greatly diminished the extent of submerged aquatic vegetation (SAV) throughout the Chesapeake Bay and other Maryland waters.
Erosion control is one of the most cost-effective pollution control programs we have. For example, in Maryland an unprotected construction site might erode at a rate of 100 tons/acre/year, which is twenty times the rate for cropland, and a hundred times that of forest. It costs $800 to $1500 to apply mulch and grass seed to an acre of construction site. These practices reduce erosion by 90% to 99%. So, assuming a typical construction site is active for a year, mulch and seeding would keep 90- to 99-tons of sediment on each acre at a cost of $8 to $17 per ton.
Maryland has 470 miles of trout streams, each of which adds about $35,000 per year to the state and local economy. A single 20-acre construction site could destroy three miles of trout stream for a decade to a century. That would work out to an economic loss of at least $1.1 million. It would cost $25,000 to apply erosion control measures which would keep 1,900 tons of sediment out of the trout stream. So the ratio of cost to benefit would be 1:42 ($25,000 cost:$1,050,000 benefit). Eventually each ton of sediment deposited in the trout stream would travel downstream.
If the sediment came to rest in a navigable channel the removal cost would be $6 to $28 per ton. The cost to remove sediment from Columbia, MD lakes runs around $175 per ton. These costs further increase the benefits of preventing erosion.
Additional benefits would come from reduced water treatment costs, other recreational and commercial fisheries preserved, enhanced waterfront property value, and on the list could go. So, as we said, erosion control is one of our most cost effective pollution control strategies.
By calling attention to opportunities for protecting exposed soil, your report will help to reduce construction site mud pollution in several very important ways.
First, in these tight budgetary times many enforcement agencies lack the personnel to visit construction sites at the frequency needed to maintain a high level of compliance. When we receive your report we will forward it to the appropriate enforcement agency. This may alert the agency to sites requiring attention which other wise might not be noted for days or weeks.
Second, we hope to instill the concept of Exposed Soil = Pollution in the general public. If this goal is achieved then exposed soil on a construction site may become just as politically incorrect as other taboos, like junk cars on lawns, burning leaves, or using a cell phone in public places. Even partial success towards this goal may motivate far greater voluntary compliance then presently occurs. The more people reporting exposed soil, the more rapidly we'll reach a threshold where voluntary compliance accelerates.
Third, your reports will allow us to monitor how well specific counties (and cities) are doing in complying with the in maintaining compliance with soil stabilization laws. By combining your reports with others we can identify those areas where additional public support is needed to help the enforcement agency achieve a higher level of compliance.
In this section we'll walk you through methods for evaluating erosion control compliance by viewing a site on the ground, from nearby public areas. You can also download a publication describing site evaluation methods: Exposed Soil = Pollution Guidance.
1. Construction Site Information: Please provide as much of the following information as you can.
Name of Construction Site: Usually found on a sign near the main entrance to the site.
Company Developing Site: Also may be found on a sign near the site entrance.
Company Contact Info: Again, this information may be found on a sign at the site entrance. Note any of the following: mailing address, phone number, e-mail, web address, or contact person.
Street Address: Most sites will not have an address so use the space in Question 2, below, to describe the location of the site.
City/Town: The borough, township, city, or postal zone in which the construction site is located.
State: The state in which the construction site is located.
County: Please note the county in which the site is located. A principal use of these reports will be to identify counties where greater public support is needed to enhance compliance with water quality protection laws.
2. LOCATION: Since most sites lack a street address, a detailed and precise description of the site location is critical. For example, describe the location with something like: on the north side of Main Street, 1/4 mile east of First Avenue. If the site is large and only a portion consists of exposed soil, then note this in the location description as well.
3. Could we get your contact information: We ask for this information in case we have questions and so we can provide you with an update on what your report and that of others has accomplished. In the next Question (#4) we ask if you wish to remain anonymous. If you do then could you at least provide your e-mail address?
4. May we share your contact information with the enforcement agency responsible for the site you reported? There's very little reason to be concerned about reporting an opportunity to protect water quality by enhancing soil erosion control. CEDS president Richard Klein has been doing this for nearly 40 years without a single negative experience; just hundreds of positive outcomes. Usually enforcement agencies will not need to speak with you, but we prefer to provide them with your contact info just in case.
5. Can you give a rough estimate of the area of the site: By area we mean how much land the site covers. We prefer that this be in acres (200 ft x 200 ft) but you could also use dimensions (feet by feet) or something like the number of NFL football field (360 ft x 160 ft or 1.3-acres) that could fit on the site or Walmart Supercenters (2.5 acres).
6. What percentage of the site is exposed soil: Of course we're talking about soil exposed once trees, grass and other plants have been stripped away. If a lot of rocks were exposed then include these in the estimate of the percentage of the site area which consists of exposed soil. You may encounter sites where a thin layer of straw mulch has been applied to exposed soil. To be effective in preventing pollution the mulch layer must be thick enough so no exposed soil shows through, as pictured to the right. So includes areas where mulch is too thin in your estimate of exposed soil.
7. What percentage of the site has some mulch, grass or other stabilization but underlying soils are still visible? To be fully effective, mulch, stone or grass must be sufficiently thick to obscure underlying soils from view. Note what percentage of the site has some stabilization but not enough to fully obscure (and protect) underlying soils.
8. Do you think its been more then two-weeks since construction started at the site? Maryland, Pennsylvania and Virginia law require essentially the same thing: Once earth-moving has ceased (temporarily or permanently) all exposed soils must be stabilized with straw mulch or other erosion control measures within a maximum of two-weeks. Areas exposed to frequent foot or light vehicle traffic, like those next to buildings under construction, should be mulched. Idle areas should be mulched and seeded with grass.
9. Are bulldozers, graders or other earth-moving equipment present on the site: The exception to the two-week stabilization requirement are those portions of a site where grading is ongoing. If grading is still occurring then the earth-moving equipment pictured here should be present on the site. If this equipment is present then note whether earth-moving is on-going. For example, if weeds are growing throughout an area of exposed soil then grading likely ceased weeks ago.
10. If you reported this site previously, do you recall when or about how long ago? This and the next question allow you to use this form to note changes on the site since filing the first (or previous) report. The actual date of your last report is best but the number of days or weeks ago would suffice.
11. If you have reported this site previously, has there been a reduction in the amount of exposed soil or other improvements? This is a two-part question. First check Yes, No, or Uncertain as to whether the area of exposed soil has changed or if other improvements have occurred, such as grass now covers areas that previously had mulch. A box is provided in Question #10, to describe changes.
12. Is there anything else you think we should know? As the question implies, this space is to note anything else of significance you observed.
Upon receiving your report we'll forward it to the appropriate enforcement agency. PLEASE provide at least your e-mail address so we can inform you of their response.
Following is the law from the three principal Bay watershed states requiring stabilization of exposed construction site soils along with a description of how to contact the office which enforces this law in each state.
Law: The Code of Maryland Regulations (COMAR 26.12.17.01.07B(3)(e)(iv)) states:
"Following initial soil disturbance or redisturbance, permanent or temporary stabilization shall be completed within seven calendar days as to the surface of all perimeter controls, dikes, swales, ditches, perimeter slopes, and all slopes greater than 3 horizontal to 1 vertical (3:1); and fourteen days as to all other disturbed or graded areas on the project site."
Enforcement Contact: Local government agencies enforce erosion and sediment control laws in 14 of Maryland's 23 counties and in eight of the larger cities. Phone numbers for these local enforcement agencies are provided at the bottom of the following Maryland Department of the Environment (MDE) webpage: Erosion and Sediment Control in Maryland.
For all other locations in Maryland call MDE at:
Law: Title 25, Section 120.22(b), of the Pennsylvania Code states:
"Upon temporary cessation of an earth disturbance activity or any stage or phase of an activity where a cessation of earth disturbance activities will exceed 4 days, the site shall be immediately seeded, mulched, or otherwise protected from accelerated erosion and sedimentation pending future earth disturbance activities."
Enforcement Contact: In Pennsylvania, construction site erosion and sediment control enforcement rests with the local Soil Conservation District or the Department of Environmental Protection (DEP) regional office. To locate the District serving your area go to: Find Your Local Conservation District. To find the nearest DEP Regional Office go to: DEP Regional Office Map.
Law: Regulation 4VAC50-30-40, of the Virginia Code states:
"Permanent or temporary soil stabilization shall be applied to denuded areas within seven days after final grade is reached on any portion of the site. Temporary soil stabilization shall be applied within seven days to denuded areas that may not be at final grade but will remain dormant for longer than 30 days. Permanent stabilization shall be applied to areas that are to be left dormant for more than one year."
Enforcement Contact: Erosion and sediment control enforcements rests with 166 local county, city or town programs. To determine the enforcement agency for your area contact the Virginia Department of Conservation and Recreation Division of Soil and Water office for your region: Regional Office Contact Information.