ERI Home IRR Home Last updated 8/10/04
Construction is fundamentally about creating a man-made structure on a piece of land. The structure is traditionally the focus of concern, and the land is reshaped as necessary to support the structure's needs. Only in rare cases is the land itself the focus, and only slightly less rarely are the land and the structure seen as equal partners. And even when both the customer paying for the work and the architect or engineer specifying the details are sympathetic to the environmental context, the main priorities for the firm hired to move the dirt and assemble the materials are likely to be centered on overcoming obstacles and getting the work completed, rather than on stewardship.
Changing this cultural mindset may be the only effective way to bring about wide-ranging environmental improvement in this sector. The alternative, using traditional regulatory methods, may be particularly difficult to apply to this sector. Inspection is difficult, since installations are transitory, operations (as opposed to practices) are nonrecurring, and organizational hierarchies among contractors are fluid and vary from job to job.
Several upcoming regulatory initiatives are likely to have a significant impact on the sector in the next few years. The most significant include air quality standards for ozone and fine particulates, and water quality standards involving Total Maximum Daily Loads (TMDLs), with stormwater runoff issues being particularly applicable to the sector.
Environmental impacts and risks
Effects of existing and future regulations on impacts
The construction sector is included under NAICS code 23. Subdivisions of interest for this analysis are listed below, with the older SIC code in parentheses:
233 (152-154) Building, developing, and general contracting
234 (161-162) Heavy construction (highways, bridges, etc.)
235 (171-179) Special trade contractors (plumbing, heating, painting, etc.)
Of these, the largest subdivision in terms of number of establishments, number of employees, net value of construction work (not counting work subcontracted out to others), and expenditures for capital equipment and for materials and supplies is the special trade contractors. The building, developing, and general contracting division is next (and accounts for the largest value of construction work if the value of subcontracts is included). Here is a summary, taken from 1997 economic census data:
|
NAICS code |
Number of establishments |
Number of employees |
Total value |
Net value |
Materials and supplies |
Capital expenditures |
| 233 (Building) | 199,289 | 1,342,953 | $382 billion | $199 billion | $84 billion | $3.0 billion |
| 234 (Highway, etc.) | 42,557 | 880,400 | $128 billion | $106 billion | $40 billion | $5.3 billion |
| 235 (Special trade) | 414,602 | 3,441,500 | $336 billion | $195 billion | $118 billion | $6.7 billion |
Although subdivisions 233 and 234 create the most obvious environmental impacts, the data indicate that the cumulative effect of all the less obvious interior work may be comparable -- perhaps even greater.
The construction sector is served by numerous organizations, including trade and professional associations of construction firms themselves and their employees, and organizations representing materials, processes, equipment, and service providers. The following represents a selection of major national organizations.
Air Quality:
Water quality:
Solid waste:
Site impacts:
Air emissions data for certain key criteria pollutants (ozone precursors) are available from the National Emission Trends (NET) database (1999), and hazardous air pollutant emissions data are available from the National Toxics Inventory (NTI) database (1996 is the most recent year for which final data are available). For the SIC codes 15xx (General building contractors), 16xx (Heavy construction) and 17xx (Special trade contractors), the total emissions for volatile organic compounds (VOC), nitrogen oxides (NOx) and hazardous air pollutants (HAPs) are as follows (in tons per year):
| SIC | Subsector | VOC | NOx | HAP |
| 1521 | Single-Family Housing Construction | 86 | 0 | |
| 1522 | Residential Construction Nec | |||
| 1541 | Industrial Building/Warehouses | 5 | 129 | 2 |
| 1542 | Nonresidential Construction Nec | 7 | 58 | |
| Total, all general building contractors subsectors | 98 | 187 | ||
| 1611 | Highway And Street Construction | 137 | 358 | |
| 1622 | Bridge Tunnel & Elevated Hgwy | 19 | 3 | |
| 1623 | Water Sewer And Utility Lines | 28 | 70 | |
| 1629 | Heavy Construction Nec | 19 | 339 | |
| Total, all heavy construction subsectors | 203 | 770 | ||
| 1711 | Plumbing Heating Air Condition | 0 | ||
| 1721 | Painting And Paper Hanging | 580 | 24 | |
| 1731 | Electrical Work | 2 | 21 | |
| 1741 | Masonry And Other Stonework | 8 | 4 | |
| 1743 | Terrazzo Tile Marble Mosaic Work | 2 | ||
| 1751 | Carpentering | 4 | ||
| 1761 | Roofing And Sheet Metal Work | 39 | 4 | |
| 1771 | Concrete Work | 1 | 17 | |
| 1791 | Structural Steel Erection | 35 | ||
| 1794 | Excavating And Foundation Work | 333 | 8 | |
| 1795 | Wrecking And Demolition Work | 392 | 14 | |
| 1796 | Installing Building Equipment | 0 | ||
| 1799 | Special Trade Contractors Nec | 1,535 | 231 | |
| Total, all special trade contractors subsectors | 2,932 | 326 | ||
| Total, all construction industry sectors | 3,233 | 1,283 |
(For some reason, HAP data are not available in these sectors except for the single category as shown.)
These numbers are not large, in comparison with typical manufacturing sectors. It is interesting to note which subcategories dominate in the construction sector. The special trades are by far the largest source of VOC emissions (paint solvents are presumably the primary reason). In the heavy construction category, highways dominate, probably because of the amount of activity, and the emissions from freshly applied asphalt. For nitrogen oxides, the relatively larger numbers most likely result from heavy equipment (Diesel) use.
The construction sector is not required to report releases or transfers to the Toxics Release Inventory (TRI).
According to an EPA fact sheet, construction and demolition debris account for 15 - 30% of all waste disposed of in landfills.
According to EPA Region 3, "Sediment runoff rates from construction sites are typically 10 to 20 times greater than those of agricultural lands, and 1,000 to 2,000 times greater than those of forest lands. During a short period of time, construction sites can contribute more sediment to streams than can be deposited naturally during several decades. ... Sediment loads from construction activities are among the greatest compared to other land uses/activities. Assessments have documented that a construction site of 4.75 acres, where only 4.2% of the site was disturbed, increased sediment yields three fold above natural levels."
Major types of environmental risk associated with the impacts include:
The impact of activities in the construction sector is different from that of most industry sectors in that the effects at any given location are acute and temporary, rather than being chronic and stationary. The nature of the construction sector's activities presents a formidable challenge to the usual modes of regulation:
At best, a given firm may carry standard practices from site to site. Encouraging widespread adoption of baseline standards for good practices might be the best way to improve environmental performance in this sector.
The main obstacle to changing standard practices in this sector would be a strong reluctance on the part of contractors at every level to make any changes that would increase costs. A manufacturer can differentiate his product and absorb higher costs by delivering greater perceived value. But a contractor generally bids on a job whose specifications are determined ultimately by the buyer. When different firms are competing for what seems to the buyer to be identical deliverables, cost becomes an overriding concern. Under the circumstances, the best way to drive change in the construction sector might be to provide incentives to the buyer to specify environmentally preferable materials and construction practices.
Another significant regulatory difficulty is a result of the non-point source nature of the air and water emission sources associated with many construction activities. Cumulative VOC emissions from paint solvents, for example, can be considerable, but there is no stack to monitor or control. Pollution prevention is the only practical approach to mitigating emissions of these types. Implementing pollution prevention would have to be done through the "special trade" firms that acquire and apply the materials. This would involve dealing with many very small operations, with a huge installed capital base.
The size of the installed capital base will also be an obstacle for the implementation of new ozone and fine particulate standards. Application of these standards to the construction sector will involve regulation of particulate and NOx emissions from heavy equipment. Various approaches that do not involve wholesale replacement of equipment may be envisioned, including control devices to be applied to the equipment, restrictions on fuels, and restrictions on hours of operation. It is likely that most such approaches will be vigorously resisted by the sector.
Effluent guidelines for Construction and Development have been proposed, and are now (as of 10/31/02) in an extended public comment period.
Sources for industry data include:
Sources on the proposed stormwater rule include:
CICA, a compliance assistance center for the construction industry with extensive coverage of applicable regulations, is located at http://www.CICAcenter.org.