UNRIVALED

STORMWATER

MITIGATION

SYSTEMS

T M

STORMVAULT™ DESIGNED TO DO IT R IGHT

Communities today are fast becoming aware of the dangerous impact stormwater runoff has on our surface and

ground waters. Stormwater runoff is harmful to the downstream environment because it shocks the water supply with

higher flows and increased sediment and associated pollutant loads. To effectively protect the environment of the

receiving waters, stormwater treatment should strive to provide both pollutant removal and flow attenuation.

The innovative design of the Stormvault™ out performs traditional stormwater treatment units which demonstrate

various deficiencies in removing pollutants and slowing runoff velocities. Products built with a flow-through design

may remove trash, debris, and large sediments, but are ineffective at removing small particles. The Stormvault™ will

effectively remove those smaller particles equal to or less than 100 microns which account for the majority of the

pollutant load associated with particulate matter in urban stormwater.* The Stormvault's™ water quality capture volume

design has the unique abil ity for capturing and retaining pollutants, preventing sediment resuspension.

Stormvault™, unlike flow-through systems, has the hydraulic capacity to attenuate peak runoff flows. Increased

runoff flows resulting from urbanization cause erosion and stream channel degradation. Experts believe that these

increased flows are at least as significant a problem as the pollutants that they carry from developed areas. High flows

sand loads from frequent events have the most deleterious effects on the riparian ecosystems. Therefore, by capturing,

treating and mitigating the impacts of the most frequently occurring runoff events, the Stormvault™ offers the greatest

environmental benefit.**Stormvault™ is designed to capture up to 85% of all runoff then

slowly release it to receiving waters. This capture-and-controlled

release is specifically designed to catch small particles and minimize

their resuspension by treating that portion of runoff containing the

highest percentage of pollutants, including "the first flush" of the

larger events and to provide peak flow attenuation to reduce

downstream erosion. Stormvault™ significantly reduces post-

development runoff flow rates, stream channel degradation, and

destruction of aquatic habitats. This high quality discharge is

accomplished irrespective of influent concentration or in flow volumes.

Stormvault™ has proven capable of providing an effluent discharge

TSS concentration of less than 20 mg/L with a 95% level of confidence.

This claim is based on over 40 storm events as documented by third

party monitoring—See:

www.people.virginia.edu/~enqstorm/storm/swgproj.htm.

Please see our web site at www.stormvault.com for complete text of

our reports from Sacramento, CA and Charlottesville, VA and our

recommended sizing criteria.

BECAUSE STORMVAULT™

IS BUILT ON SOUND

ENGINEERING PRINCIPLES

AND BACKED BY EXTENSIVE

HYDRAULIC LABORATORY

AND FIELD TESTING, IT

ADDRESSES PREVIOUS

DESIGN SHORTCOMINGS.

THE RESULT: NOT ONLY A

NEW PRODUCT, BUT AN

ENTIRELY NEW APPROACH,

AND A STRUCTURAL

TREATMENT UNIT THAT

ACTUALLY WORKS!

Urbonas, B. and Stahre, P. (1993). "Stormwater:

Best Management Practices and Detention,"

Practice Hall, NJ, USA.

Schuler, T.R. (1994). "Watershed Protection

Techniques," Center for Watershed Protection,

Silver Springs, MD, USA.

*

**

STORMVAULT™

RESEARCH AND

DEVELOPMENT

team

W ith more than 35 years of leadership in developing precast

concrete products, Jensen Precast made a commitment

to manufacture and deliver a superior stormwater

treatment system.

In 1998, the company contracted with renowned consultants,

engineering f irms and universities to design the optimal vault

for present and future stormw ater mitigation.

The resulting product, Stormvault™ ,

achieves Jensen´s lofty goal. Its

unprecedented patented design

provides stormwater capture and

treatment that surpassed expectations

and is well suited for satisfying Phase II

NODES regulatory guidelines for urban

areas. W e believe Stormvault™ more

than meets its intended function as the

best structural stormw ater mitigation

system f ound on the market today.

See for yourself by calling Jensen

Precast at (800) 648-1134. W e´ll send

you the Stormvault™ design manual,

complete with research, test data and

design specif ications.

STORMVAULT™ SUPERIOR STORMWATER TREATMENT

W r i g h t W a t e r E n g i n e e r s I n c.

Jonathan E. Jones, P. E.

Andrew Earles, Ph. D.

M ark Van Nostrand, P. E.

John O´Brien

Co lo r a do St a t e U niver sit y,

Department of Civil Engineering:

Dr. Steve Abt, P. E. , Director of

Hydraulics Laboratory

Tom Brisbane

U niver sit y o f V ir g in ia ,

Department of Civil Engineering:

Shaw L. Yu, Ph.D.

Elizabeth Fassman, M . S.

U rban W atersheds:

Ben R. Urbonas, P.E., Outside

Technical Reviewer & Advisor

‡ WWEF (1998). " Urban Runoff Quality M anagement," WEF Manual of Practice No.23

ASCE Manual and Report on Engineering Practice No.87

Manker, P.W., et al, (1998). Flood Hazard News‡‡

FLO

W

TIM E

Post-development hydrograph,uncontrolled runoff with highrunoff coeff icient

Pre-developmenthydrograph, runoff withlow runoff coeff icient Post-development

hydrograph, with properlysized Stormvault™ ††

†

††

Minton, Gary (2002). " Stormwater Treatment,"Gary Minton, Seattle, WA, USA.A properly sized Stormvault™ can reduce Post-developmentrunoff flow rates to less than Pre-development values.

00

2 0

4 0

6 0

8 0

1 0 0

0 2 0 4 0 6 0 8 0 1 0 0 1 2 0 1 4 0 1 6 0 1 8 0 2 2 02 0 0 2 4 0 2 6 0 2 8 0

ComparativeLine ofPerformance© †

Sacramento2001Stormvault™

V irginia 2001Stormvault™

V irginia 2002Stormvault™

The Jensen Precast Stormvault™ is designed to meet the intent of Phase II NPDES Maximum Extent Practicable (MEP) for discharge

to waters of the United States through the management and treatment of site runoff by diverting the design water quality capture

volume into the vault. This Water Quality Capture Volume (WQCV) sizing methodology is based upon recommendations of two

of the most prominent civil engineering professional associations: the American Society of Civil Engineers (ASCE) and the Water

Environment Federation (WEF).‡ This approach calculates the fraction of the runoff that is treated after processing each runoff

event against the Stormvault™ emptying time. For optimal performance the Stormvault™ can be sized using the maximized

WQCV, the point where increasing capture volume results in a diminishing number of storm runoff events fully captured. This

volume represents not only the point of diminishing returns to economically treat storm runoff volume; it also represents the point

at which the vast majority of pollutants have been captured. Because of its many unique features, including " volume control" and

a " vertically stacked water column" , Stormvault™ has been granted a United

States Patent # 6,350,374 with other patents pending.

As urbanization and impervious surfaces increase, the quantity of runoff events

from small storms increases; as little as 0.08 to 0.12 inch of rainfall is needed to

cause initial runoff within an urban watershed.‡‡ The majority of small storms

on undeveloped land may not produce significant runoff however, post-

development precipitation can create considerable detrimental runoff events.

The Stormvault™ system has proven capable of reducing the post-development

runoff Q to near pre-development levels and providing TSS and nutrient reductions

comparable to high quality " final treatment" natural systems as listed on the

EPA/ASCE BMP database. When compared to the Line of Comparative

Performance© created by Dr. Gary Minton, Ph.D., P.E. illustrating the median

performance data of grassy swales, wet ponds and sand filters, over 70% of

the Stormvault's™ monitoring data points were above this median

performance curve. The Stormvault™ clearly rivals the performance of these

public domain stormwater technologies by effectively removing TSS from

stormwater runoff to near irreducible levels. The Stormvault™ eliminates

traditional disadvantages of natural systems such as extensive surface area

requirements, excessive thermal pollution, attractive nuisance liabilities,

mosquitoes and long-term maintenance access and disposal concerns. The

Stormvault's™ unrivaled third party monitoring data from over 40 individual

storm events has been reviewed and accepted by the USEPA/ASCE BMP database.

Please see www.bmpdatabase.org.

STORMVAULT™ OPT IM I ZES CAPTURE AND HOLD

STORMVAULT™

PERFORMANCE AND THE

LINE OF COMPARATIVE

PERFORMANCE©

RE

MO

VA

L E

FF

ICIE

NC

Y (

%)

I N F L U E N T T S S ( m g / L )

STORMVAULT™ WITH RUNOFF CONTROL

CONTROL ORIFICE

TRAPEZOIDAL EXIT BAFFLE

EFFLUENT CONTROL TEE

LARGE OUTLET SCREEN

INLET PIPE

DIVERSION WEIR

OUTLET

SEDIMENT BAFFLE

MULTIPLE ACCESSES

ENERGY BAFFLE

STORMVAULT™ FEATURES AT A GLANCE

Stormvault™ is a USA & C anada Patent Pending System.

W ith its sizing f lexibility, Stormvaultª of fers excellent economy of

scale. Add to that Jensen Precast´s f ield supervision, delivery and

assembly services, and more than 35 years in the industry and you

will realize exceptional value and service. See for yourself by calling

Jensen Precast at (800) 648-1134.

TM

w w w. st o r mva u lt . co m

Stormvault™ is a trademark of Jensen Precast and is covered

under U.S. Patent No. 6350374 and other

U.S. and Canadian patents pending.

Copyright © 2001-2003, Jensen Precast, a ll r ights reserved.

JE N /V 4/0603

w w w .jensenpr eca st . co m

O r e g o n

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B end, O R 97701

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A r i z o n a

1441 N o r t h V IP B lvd.

Ca sa G r a nde, A Z 85222

(520) 316-0373

H a w a i i

1255 N u u a nu A ve.

Su it e C-104D

H o no lu lu , H I 96817

(808) 528-1175

S o u t h e r n C a l i f o r n i a

14221 Sa n B er na r dino A ve .

Fo nt a na , CA 92335

(909) 350-4111(800) 257-6100

N o r t h e r n C a l i f o r n i a

5400 R a ley B lvd.

Sa cr a ment o , CA 95838

(916) 991-8800(800) 843-9569

7980 H ighw a y 99

P. O . B o x 1210

Lo s M o lino s, CA 96055

(530) 384-2763

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(775) 359-6200(800) 648-1134

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3853 Lo see R o a d

N o r t h La s V ega s, N V 89030

(702) 649-0045