CENews.com - Project Case Study: Alternative approach = - For the Business of Civil Engineering

		send=20 to friend \| \| printer friendly \| purchase reprint

SEARCH=20 CENews.com

=20

WELCOME

Home Page

About=20 CENews.com

SUBSCRIBE to Magazine

SUBSCRIBE to eNewsletter

EDITORIAL

EVENTS

Land Development East

Land Development West

AEC Tech=20 Strategies

Best Firm Summit

Event=20 Calendar

RESOURCES

NEW! Microsites

Civil Engineering Careers

ADVERTISING

CONTACT US=20

= =20 =20

Receive new = article=20 notifications via Civil Connection = e-news! Sounds = great, but=20 what's Civil Connection?

Enter Email = Address:

CENews.com = Feature Article |=20 Posted: Thursday, November 10, 2005

Project Case = Study:=20 Alternative approach

A new golf course development uses onsite cluster system below = the=20 fairways for wastewater treatment.

BY DENNIS F. HALLAHAN, P.E.

Project
Sunserra at Crescent Bar, = Quincy,Wash.

Design engineer
Eco-Nomic Environmental = Services,=20 Ephrata,Wash.

Product application
An onsite wastewater = system=20 for a 207-home resort community uses Infiltrator Systems' chambers = for=20 drainfields beneath a golf course's fairways.

Sunserra at Crescent Bar is a resort community of 207 = individual and=20 clustered residential homes bordering a new golf course. It is = located on=20 the Columbia River in Quincy, Wash., on a dogleg portion of = Crescent Bar=20 surrounded by steep basalt cliffs. The golf course was designed in = the=20 center of the development, separating the singlefamily homes.

Prior to the addition of the golf course and the expansion of = the=20 development, the Washington Department of Ecology imposed = restrictions on=20 the use of enlarged lagoon systems for wastewater treatment, a = design=20 previously used in this area. This was the catalyst for the = developer,=20 Sunserra Construction LLC, to push project engineers to search for = an=20 alternative approach that would enable them to obtain approvals to = complete the development.

Project challenges and development

The nature of the development and project timing required that = the=20 onsite septic system and the drainage lines for the golf course = and=20 clubhouse needed to be installed simultaneously beneath the = fairways of=20 the golf course. Drip irrigation, surge tanks, as well as = oversized=20 drainfields, were considered. The final design specified a = gravelless=20 system using Infiltrator Systems' Quick4 standard chambers in = alternating=20 drainfields and reserve areas (to use for replacement systems in = the=20 unlikely case that the primary system fails). In this project, = replacement=20 systems were constructed up front because it was less expensive = than=20 potentially shutting down the golf course to install a new system = in the=20 reserve area.

Because the drainfields were designed under the golf course = fairways,=20 long-term function and reliability were critical factors. The golf = course=20 owners did not want the system to be accessed during the golf = season=20 because of system failure or for repairs, as this would require = the golf=20 course to close and pose a major economic hardship.

Another factor that complicated system design was the potential = for=20 unpredictable and erratic flows because of the resort nature of = the=20 development with a fluctuating population. The chosen design = offered the=20 greatest level of surge protection without the additional expense, = safety,=20 reliability, and aesthetic problems associated with surge = systems.

Rugged terrain also posed a challenge as engineers worked to = create a=20 system that could follow natural drainage over rugged terrain to = pump to=20 the chambers. In addition, another hurdle that needed to be = overcome was=20 the integration of 5 miles of distribution lines with the golf = course's=20 irrigation and drainage lines.

Coordination between the golf course designer, Reven Fonteneau; = the=20 engineer, Certified Designer John Glassco of Eco- Nomic = Environmental=20 Services; Grant County regulators; the developer; and the = excavating=20 contractor Dennis Freese and Sons was required throughout the = system=20 design, approval process, and installation.

=E2=80=9CIn the over 250 golf courses I have designed, this is = the first in=20 which the golf course design and the resort wastewater treatment = system=20 were integrated in this way,=E2=80=9D said Fonteneau.

Regulatory compliance and system design

The soils in this area of the Columbia River Gorge are = typically=20 100-foot deep, medium and fine sand deposits with wastewater = application=20 rates of about 0.8 gallons per square foot per day. The Grant = County=20 regulations required a maximum system flow of 3,500 gallons per = day (gpd)=20 per system (17 systems in total). In response to this, Glassco = designed=20 each system to handle a capacity of 3,120 to 3,480 gpd. The system = design=20 includes 17 primary systems (serving about 15 homes each) and 17=20 replacement systems including drainfields, using a total of 7,122 = Quick4=20 Standard Chambers. According to county regulations, flows from the = units=20 were not allowed to combine. The design factor for each system was = adjusted to use a single pump model through the use of automatic=20 distributing valves and transport lines constructed of multiple = diameters=20 of pipe.

County regulations stipulated that the septic system could be = no deeper=20 than 36 inches. In addition, a 16-inch-deep irrigation system for = the golf=20 course needed to be designed and built above it.

All of the greens and traps for the golf course have = independent=20 drainage systems constructed in concert with the septic = systems.

In addition to the Quick4 Standard Chambers, the design = includes=20 seventeen 6,000-gallon septic tanks, sixteen 2,500-gallon pump = chambers,=20 two 1,500-gallon additional tanks, and 334 custom-cast concrete = vaults all=20 provided by Wilbert Precast of Spokane. Orenco Systems, Inc., = provided=20 pumps, controls, and 17 automatic distributing valves for the = project. HD=20 Fowler Co. of Wenatchee provided the pipe and fittings, which = include more=20 than 5 miles of 1-inch-diameter, lateral piping and almost 3 miles = of=20 effluent and transport lines following the septic tanks.

Project installation began in March 2005 and was completed in = May. The=20 lowest house in each group has the septic tank closest to it. = Sewage from=20 the homes flows from the cluster's septic tank to the pump = chambers via=20 4-inch PVC pipe. Each drainfield is 40 feet by 240 feet and has = six,=20 time-dosed zones. The drainfields are 36 inches deep with = transport lines=20 at a shallower depth and the golf course's 16-inch irrigation = system above=20 and below them. The distribution and check valves are mounted at = the=20 drainfield and are supplied with two transport lines, one for each = pump in=20 the chamber.

When the pump shuts off, the check valve opens and drains the = line.=20 Each drainfield is custom designed to accommodate the differing = transport=20 line sizes. The replacement drainfields handle the peak flows,=20 safeguarding the golf course from the possibility of a weekend=20 overload.

At Sunserra, Eco-Nomic Environmental Services provided tried = and true=20 engineering principals to arrive at a new, unique solution.

Many systems were evaluated, such as drip irrigation, and when = a=20 cost-benefit analysis was performed, the chamber system provided = the most=20 benefit at the least cost. Everyone involved with the project, = including=20 county regulators and the construction contractor, were open to = trying new=20 products and ideas that resulted in the system being placed under = the=20 fairways with the construction of the replacement systems up = front. This=20 innovative, creative, and open thinking made the project possible. =

Dennis F. Hallahan, P.E., is technical director for = Infiltrator=20 Systems, Inc., Old Saybrook, Conn. He can be contacted at 800- = 221-4436 or=20 via e-mail at dhallahan@infiltrato= rsystems.net.

= =20 =20

Receive new = article=20 notifications via Civil Connection = e-news! Sounds = great, but=20 what's Civil Connection?

Enter Email = Address:

New on=20 CENews.com

Advertisment

Who will understand=20 technology?

London's super sewer to handle=20 CSOs

Home Depot pays stormwater=20 fine

TRB Annual Meeting sessions available=20 online

Send your article ideas, news items, and = comments to=20 mailto:info@CENews.c= om?subject=3DCENews.com!=20

	London's super=20 sewer to handle CSOs
	Home = Depot pays=20 stormwater fine
	TRB = Annual Meeting=20 sessions available online
	Keynote = highlights=20 sustainable real estate
	More=20 news

	ITE = 2008 Technical=20 Conference March 2008
	ACI = Spring 2008=20 Convention March 2008
	Carlson = Silver=20 Anniversary User Conference April 2008
	All=20 events


			CENews.com is part of the = ZweigWhite=20 network of Architecture, Engineering, and Construction Web sites

			ABOUT=20 ZWEIGWHITE \| CONSULTING \| BOOKSTORE \| CONFERENCES \| TRAINING \| MEDIA
			=A9 ZweigWhite Information = Services \|=20 CONTACT US=20