Socio-Economic Benefits Study: Scoping the Value of CORS and GRAV-D (2009)


This is a scoping study to provide the basis for a full analysis of the socio-economic benefits of CORS and GRAV-D to the United States. The objective was to address the questions:

  1. Who benefits from CORS, GRAV-D or both?
  2. What is the nature and basis of these benefits?
  3. What methodology is appropriate for estimating the value of CORS and GRAV-D to society?
  4. What information is needed to estimate the values and how can it be obtained?
  5. What are the estimated order of magnitude values of socio-economic benefits for CORS and GRAV-D?


The NGS Continuously Operating Reference Station (CORS) system is the cornerstone of the geometric component of the National Spatial Reference System (NSRS). GRAV-D. Gravity for the Re-definition of the American Vertical Datum is a project whose goal is to redefine the vertical datum of the United States and replace geodetic levelling in large areas with GPS measurements and a gravimetric geoid model to determine orthometric heights more efficiently and accurately than with the current datum.

Geographical scope


Non-quantified impacts

Not identified

Quantifiable impacts

An illustrative order of magnitude of benefits of NSRS is AUD 2.4 billion per year. This is derived by building on revenue from private surveying and mapping, adding assumptions for the government and not-for-profit sectors and adding a factor for societal benefits. The AUD 2.4 billion per year, extended over 15 years and discounted at 7%, leads to a present value for the NSRS of AUD 22 billion. If benefits grew at 7% per year, the discounted value would be AUD 36 billion.

An estimate of CORS benefits is made by adjusting the NGS estimates to account for the fact that not all users would be willing to pay the full cost of obtaining data from a station and adding a factor for societal benefits. The order of magnitude of CORS benefits is estimated as AUD 758 million per year. The present value of these benefits, discounted at 7% over 15 years, is AUD 6.9 billion even without future growth. If benefits grew at a 15% annual rate, less than the recent growth rate of 22%, the order of magnitude of the present value of CORS benefits over the next 15 years would be AUD 18.5 billion. These figures do not include deductions for government and private costs of providing CORS data.

The value of benefits that GRAV-D might have under current conditions is estimated based on avoided costs of long line levelling and benefits of improved floodplain mapping through building standards in vulnerable areas and avoidance of vulnerable areas. Business receipts of firms marketing the product lines “geophysical data acquisition, processing and interpretation” are used in estimating avoided costs of long line levelling. Assumptions are made for the size of revenues of governments and not-for-profit organisations relative to those of private firms, proportions of the activities of each sector that consist of long line levelling and of benefits above user costs (consumer surplus) and societal benefits. The order of magnitude of these benefits of GRAV-D is estimated as AUD 282 million per year. Discounting annual benefits of AUD 282 million over 15 years at a rate of 7% yields a present value of benefits of GRAV-D from avoiding costs of long line levelling of AUD 2.6 billion.

A conjectural estimate of the benefit of GRAV-D for floodplain management under current conditions is AUD 240 million per year. This is based primarily on the avoided cost of flood damage to buildings. The present discounted value of benefits of AUD 240 million per year over 15 years is AUD 2.2 billion. Combining the AUD 2.6 billion estimate of the benefits of GRAV-D in avoided costs of long line levelling with the AUD 2.2 billion from improved floodplain management yields a combined conjectural estimate of the present value of benefits of GRAV-D over 15 years of AUD 4.8 billion. Properly valuing GRAV-D requires quantifying its benefits under scenarios for its evolution under future conditions.



Study type

Industry estimations based on expert opinion

Economy sector

Water, Infrastructure (Transport), Infrastructure (Energy), Public Safety and Security, Insurance, Real Estate and Land Administration, Design and Construction, Public Sector Local Government, Public Sector Central Government, Agriculture