Network corrected real-time is a technological approach to high precision GPS/ GNSS positioning that has been theorized about, studied, experimented with, and implemented in various academic, scientific, and commercial forms for nearly a decade. Many of the various approaches share the fruits of past research, algorithms, and technological tools; some which are in common.
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My dictionary tells me that "sustainable" means "able to be maintained", and my textbooks tell me it means "exploiting natural resources without destroying the ecological balance of a particular area." Combining these concepts gives us an opportunity to apply the "s" word to more than figuring out how to get potable water to the explosive development in our arid southwest. The news is full of intriguing variations and new approaches to land use that could allow us to address our clients' projects a little differently.
One solution to the problem of preserving the environment and human use of it comes from the fishermen of Maine, whose concern about preserving their livelihoods has spurred them to join with towns and residents in buying the state's working waterfronts. Fishermen, ferry operators, and boat builders historically have not owned the docks and wharves where they work. With high demand in the real estate market for waterfront properties, communities are at risk of losing their businesses and their public access to the water. Maine's Working Waterfront Access Pilot Program made its first awards this year, $1.2 million in matching grants to six communities and organizations, and is reviewing proposals for a second round of grants to be awarded in July. Here, sustainability literally translates into life or death for seaside communities.
Another resolution is something called "the sustainable trail initiative", an internationally applied method recently introduced here in the Philadelphia region. The city has about 9,200 acres of open space in the 63 regional and neighborhood parks making up Fairmount Park. One of the most heavily used areas encompasses about 57 miles of trail through the 1,800 acres of Wissahickon Park, where numerous fall line trails run steeply down hill. When it rains, these trails become streams, eroding the trail, the hillside, and anything else in the path of water heeding the call of gravity. As a little geological background, this area is in the Piedmont uplands, with outcrops of metamorphic rocks (especially the Wissahickon schist so prevalent in local construction) that were formed from compacted clay-rich sediments deposited in the shallow ocean covering Pennsylvania about 600 to 460 million years ago. With this watery beginning, it should be no surprise that underground streams surface as springs and creeks throughout the parks and the city.
Our trails are so worn down after over a century and a half of use that we have become accustomed to walking in what amount to shoulder-high ditches and canyons. Where trail users (hikers, mountain bikers, and horseback riders) circumnavigate the mushier spots, the growth along the former trail edges can no longer hold water in the soil, or even hold those soils in place, compounding the problem. For us, the application of sustainable trail concepts began with closing some existing trails that could not be redesigned, to allow them to recover. Filling some eroded trails with organic matter brought them close to the grade of the surrounding land, and contouring other areas facilitated stormwater dispersal, slowing flow to allow percolation. Designs for existing and new trails meander more than old trail configurations, in part using logs and boulders as human traffic calmers.
Elsewhere in southeastern Pennsylvania, another stretch of park is temporarily closed to the public because of erosion. Since the first European colonists settled along the streams in Penn's Woods, structural methods have reigned supreme in attempting both to utilize the water and to control it. Stone walls meant to "reclaim" the banks, generate power, and hold back flood waters have not proved as strong as nature's powers, and even some of the newer constructions have failed in the face of the last several years of hurricane-induced water flow. In some areas, the undermined walls have collapsed. Elsewhere, intermittent streams now run through steep-sided gullies that erode with each new storm, whether of hurricane force or more normal spring downpour.
We should remember that water, left to its own devices, generally creates its own 30-degree or less banks. Last summer I asked a homeowner about the stone-lined slope on the opposite side of the creek from her refurbished mill-house. Large boulders littered the area, both in the water and above the top of bank, and I wondered about them. She told me that her attempt to gain "just a few more feet of usable yard" by sloping the bank to 45 degrees and lining it with those boulders had failed completely, and that the late-summer storms of the prior year had ripped her construction back to its current and original 30-degree angle. The scattered boulders were nature's way of reminding her that money and human labor can't always overcome the elements.
Returning to my township parks' streams, their banks are being bulldozed back to gentler slopes, recreating floodplains and holding them in place with water-loving plants and trees. The unrestricted streams will be able to jump the banks during high flow, rather than being forced into the narrow, hard-walled runs that currently increase water height and velocity. Outside of the park's limits, homeowners along the same streams are extending the work. Habitat is the primary concern inside the park; preserving properties from erosion is a large motivator outside of it.
Sustainability takes many forms, and another economic version of it is making its way across the country in the form of flood control or storm water utility fees. In most localities, these are dedicated funds for the repair or replacement of drains and pipes. Avoiding the dreaded label of "tax", some proponents note that sewer rates can decrease in areas where storm water fees are in place. Wilmington, Delaware bases its fees on the amount of a property's impervious surface. Philadelphia instituted similar fees about 40 years ago, but because they are based on the size of the water-meter connection, some of the worst contributors to runoff (such as parking lot owners) pay nothing. Watershed protection is inspiring a regional search for a solution, since the city's neighbors, elevated above Philadelphia, contribute to the city's storm water problems.
While these examples relate primarily to water, we can extrapolate from them to develop other sustainable, sometimes non-standard, approaches to land use challenges.
Wendy Lathrop is licensed as a Professional Land Surveyor in NJ, PA, DE, and MD, and has been involved since 1974 in surveying projects ranging from construction to boundary to environmental land use disputes. She is a Professional Planner in NJ, and a Certified Floodplain Manager through ASFPM.
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Editorial: Machine Control Redux
I have received a fair amount of response to my July editorial about machine control. Responses included those who agree with me as to the inevitable impact it will have on the future of surveying and those who accuse me of selling out. Notwithstanding those states such as California that require a .... Read the Article
Point to Point: The Pincushion Dilemma
Pincushion corners result when two or more markers exist identifying the same property corner. If set by surveyors, they are invariably the result of different interpretations of evidence, whether justified or not. The measurati have almost universally denounced them as further evidence of rank-and.... Read the Article
The WowFactor: OfficeSync
Drastic changes in the U.S. economy, including the recent runup in the price of gasoline, have had a direct effect on how firms use technology to remain competitive. Civil engineering and land surveying firms have had to make serious decisions, and time management is ... Read the Article
In Search of Monhegan's Letters
Monhegan Plantation is an island ten miles off the coast in the Gulf of Maine. An artists' haven with a rich history in fishing, the island's average population of 75 residents explodes each summer with the opening of ... Read the Article
Towers of Power - Surveyors Locate Next Generation Transmission Lines
As originally planned, the Eastern Plains Transmission Project, one of the country's largest power expansion projects in progress, is expected to ultimately deliver about 1,000 miles of .... Read the Article
A Visit to the South Carolina Geodetic Survey
One of the hold-ups in the implementation of Real Time Networks (RTNs) for machine control has been the vertical accuracies. That being the case, when one of our writers, Joe Betit, told me that he had heard that the South Carolina .... Read the Article
In Memoriam: John E. Chance, 1924-2008
A legend within surveying circles along the Gulf of Mexico and in the petroleum and pipeline industries worldwide, John Chance died May 1, 2008 at his home in Lafayette, Louisiana. "Mr. John," as he was affectionately known by his friends, was born John Edward Chance on ... Read the Article
FeedBack
More on the Schuylkill Center Wendy Lathrop's valuable article "Where There's a Will... " [Sept. 2007] couples the Orphans' Court activities of the Barnes Foundation and the Schuylkill Center for Environmental Education (SCEE). From a legal point of view the breaking of ... Read the Article
Software Review: General CADD
Backward compatibility has always been one of the things that make a good solid product. General CADD started out as an inexpensive CADD program working in DOS. Generic CADD was the name and it made it possible for surveyors who could not afford the very... Read the Article
Survey Reports: Preparing a Survey Report - Part 4: FAQ
This is the fourth article in a series of articles suggesting formats and contents of a survey report. Previous articles dealt with opinions on the location of corners and boundaries [Feb. 2008]; encroachments, gaps and overlaps [Mar. 2008]; and limitations of of the surveying ... Read the Article
Vantage Point: Water Over the Dam and Down the River
What's old is new, and it's all wet. It may seem to be a "modern" approach to look beyond our own municipal boundaries to see what is happening on the other side of an invisible jurisdictional line that will affect flooding and stormwater on our side of that line. But awareness of ... Read the Article
• 15th Annual GeoTech - October 7-8, 2008, NOAA’s Auditorium and Science Center in Silver Spring, MD. Hosted by Potomac Region of the American Society of Photogrammetry and Remote Sensing and co-hosted by the NGS, 1 day of Workshops taught by experts, and 1 day of Technical sessions.,
• Geography in Las Vegas - March 22–27, 2009. Join 8,000 geographers, GIS specialists, and environmental scientists from around the world in Las Vegas for the very latest in research, policy, and applications in geography, sustainability, and GIScience, during the annual conference of the Association of American Geographers.
• California Land Surveyors Association 2009 Conference - March 28-April 1, 2009, Hilton San Diego Resort (Mission Bay).
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• SPAR 2009 - March 30- April 1, 2009, Hyatt Regency Hotel, Denver, Colorado. SPAR 2009 will focus on best practices for using 3D imaging technologies to design and deliver capital projects as well as operate, modify and maintain production, manufacturing and infrastructure assets.
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