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EXECUTIVE SUMMARY
City Council Meeting: February 5, 2019
AGENDA ITEM: Rosemount High School Parking Lot, CP
2018-07: Approve Stormwater
Maintenance Agreement with ISD 196
AGENDA SECTION:
Consent
PREPARED BY: Stephanie Smith, PE, Assistant City
Engineer AGENDA NO. 6.n.
ATTACHMENTS: Stormwater Maintenance Agreement APPROVED BY: LJM
RECOMMENDED ACTION: Motion to Approve Entering into an Agreement with ISD 196
for Stormwater System Maintenance and Easement.
BACKGROUND
Independent School District (ISD) 196 has constructed improvements on their Rosemount High School,
Middle and Elementary School site in Rosemount. Improvements included new parking lot configuration
and stormwater improvements including three underground stormwater treatment systems.
Consistent with the requirements of the City’s MS4 permit and similar to other privately maintained
underground stormwater facilities in Rosemount, the City has required the District to enter into an
agreement for ongoing maintenance of their stormwater system. Per the attached agreement, the District
will inspect and maintain their stormwater facilities at their expense. The District will submit annual
inspection reports to City staff for review and grant the City easement to access the system.
The Stormwater System Maintenance and Easement will be on the agenda for approval by the ISD 196
Board on February 11, 2019. The City Attorney has reviewed and concurs with agreement.
RECOMMENDATION
Staff recommends the City Council approve entering into an agreement with ISD 196 for Stormwater
System Maintenance and Easement.
1
Stormwater System Maintenance and Easement Agreement
With Access Rights and Covenants
Between the City of Rosemount and Independent School District 196
This Maintenance Agreement (“Agreement”) is made by and entered into as of the 11th
day of February 2019, by and between the City of Rosemount, a Minnesota municipal
corporation (the "City") and Independent School District #196 (the “District”), a
Minnesota public school district.
RECITALS
WHEREAS, the District is the fee owner of certain real property (the "Property")
located in Dakota County, Minnesota, legally described per Exhibit C, Parcel ID Numbers
34-03700-06-040 (Rosemount High School) and 34-03700-06-210 (Rosemount
Elementary/Middle School);
WHEREAS, the District will maintain the stormwater management system (herein
referred to as “stormwater system” or “system”) in accordance with the provisions of
this agreement. For the purposes of this agreement, the stormwater system is defined
as those underground facilities depicted on Exhibit A over which an easement is granted
by this agreement;
WHEREAS, the parties now wish to set forth mutual obligations and conditions
relating to the stormwater system, the location of which is shown on Exhibit A attached
hereto; and
WHEREAS, the City has requested, and the District has agreed, to grant the City
a permanent, non-exclusive drainage and utility easement over the portion of the
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Property in which the stormwater system is located solely for the purposes of allowing
the City access in order to maintain and inspect the system when necessary, as detailed
more fully in paragraph 4. The easement area is illustrated in Exhibit A.
NOW, THEREFORE, in consideration of mutual covenants of the parties set forth
herein and other valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties agree as follows:
1. Term. This Agreement will remain in effect for fifty years from the date it
is fully signed by the City and the District unless terminated for any reason by either
party after 60 days’ notice to the other party.
2. Routine Maintenance of the Stormwater System. The District, for itself and
its successor or assigns, agrees to maintain the stormwater system and observe all
drainage laws governing the operation and maintenance of the system. The District shall
inspect and perform routine maintenance of the stormwater system as described in
Exhibit B. The District shall also repair or replace any components of the system deemed
necessary during routine maintenance. The District shall keep a record of all inspections
and maintenance activities and submit such records annually to the City.
3. Maintenance Costs. The District shall bear all costs associated with routine
maintenance, repairs or replacement items for the system. It is agreed that the
stormwater system, as defined in this agreement, comprises only District-owned
improvements and that nothing in this agreement shall be interpreted as requiring
District to inspect, maintain, repair or replace, or bear any of the cost of inspecting,
maintaining, repairing or replacing, any other system, facility or improvement, including
but not limited to City stormwater pipe.
4. City's Maintenance Rights. The City may maintain the stormwater system
if the City reasonably believes that the District has failed to meet its maintenance
obligations under this Agreement and such failure continues for 30 days after the City
gives the District written notice of such failure or, if such tasks cannot be completed
within 30 days, after such time period as may be reasonably required to complete the
maintenance provided that District is making a good faith effort to do so. The City's
notice shall specifically state which maintenance tasks are to be performed. If District
does not complete the maintenance within the time required in the City's notice, the
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City may enter the Property as may reasonably be necessary to perform or contract for
the maintenance. In such case, the City will send an invoice for the reasonable
maintenance costs to the District, which shall include all reasonable staff time,
engineering and legal, and other reasonable costs and expenses incurred by the City. If
the District fails to reimburse the City for the costs and expenses within 30 days of the
date of the invoice, the City may assess said costs against the District’s Property. The
District acknowledges that the maintenance work performed by the City regarding the
stormwater system benefits the District Property in an amount that exceeds the
assessment and hereby waives any right to hearing or notice and the right to appeal the
assessments otherwise provided by Minnesota Statutes, Chapter 429.089.
Notwithstanding the foregoing, in the event of an emergency, as determined by the city
engineer, the 30-day notice requirement to the District for failure to perform
maintenance, is waived in its entirety by the District, and the District must reimburse
the City for the costs and be subject to assessment by the City for the costs in the same
manner as if the written notice had been given.
5. Hold Harmless. To the extent permitted by Minnesota law, the District
agrees to indemnify and hold harmless the City and its agents and employees against
any and all claims, demands, losses, damages, and expenses (including reasonable
attorneys' fees) arising out of or resulting from the District's, or the District's agents' or
employees' negligent or intentional acts, or any violation of any safety law, regulation
or code in the performance of this Agreement, without regard to any inspection or
review made or not made by the City, its agents or employees or failure by the City, its
agents or employees to take any other prudent precautions, except to the extent of
intentional or grossly negligent acts of the City, its employees, agents and
representatives. In the event the City, upon the failure of the District to comply with any
conditions of this Agreement, performs said conditions pursuant to its authority in this
Agreement, to the extent permitted by Minnesota law, the District hereby agrees to
indemnify and hold harmless the City, its employees, agents and representatives for its
own negligent acts in the performance of the District's required work under this
Agreement, but this indemnification shall not extend to intentional or grossly negligent
acts of the City, its employees, agents and representatives.
6. Costs of Enforcement. The District agrees to reimburse the City for all
reasonable costs incurred by the City in the enforcement of this Agreement, or any
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portion thereof, including court costs and reasonable attorneys' fees after providing
written notice to District and a reasonable opportunity to cure.
7. Rights Not Exclusive. No right of the City under this Agreement shall be
deemed to be exclusive and the City shall retain all rights and powers it may have under
Minnesota Statutes, Chapter 444 to acquire, construct, reconstruct, extend, maintain
and otherwise improve the stormwater system.
8. Notice. All notices required under this Agreement shall either be
personally delivered or be sent by United States certified or registered mail, postage
prepaid, and addressed as follows:
a) as to District: Independent School District #196
Attn: Mike Schwanke
14309 Diamond Path
Apple Valley, MN 55124
b) as to City: City of Rosemount
Attn: City Administrator
2875 - 145th Street West
Rosemount, MN 55068
with a copy to: Kennedy & Graven
Attn: Rosemount City Attorney
470 U.S. Bank Plaza
200 South Sixth Street
Minneapolis, MN 55402
or at such other address as either party may from time to time notify the other in writing
in accordance with this paragraph.
9. Amendment. This Agreement may not be amended without the express
written consent of both parties.
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10. Successors and Assigns. All duties and obligations of District under this
Agreement shall also be duties and obligations of District's successors and assigns. The
terms and conditions of this Agreement shall run with the Property.
11. Effective Date. This Agreement shall be binding and effective as of the
date first written above.
12. Recitals. The recitals are incorporated as a part of this Agreement.
IN WITNESS WHEREOF, the parties hereto have executed this Agreement.
CITY OF ROSEMOUNT
By _______________________________ Date:
Its City Administrator
STATE OF MINNESOTA )
)ss.
COUNTY OF __________ )
The foregoing instrument was acknowledged before me this _____ day of
________________, 20__, by ____________________________.
____________________________________
Notary Public
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INDEPENDENT SCHOOL DISTRICT 196
By: _______________________________ Date:
Its ________________________
STATE OF MINNESOTA )
)ss.
COUNTY OF __________ )
The foregoing instrument was acknowledged before me this _____ day of
________________, 20__, by ____________________________.
____________________________________
Notary Public
Exhibit A
Exhibit B
Exhibit C
This Instrument Was Drafted By: ANDERSON-JOHNSON ASSOCIATES, INC.
7575 GOLDEN VALLEY ROAD, SUITE 200
MINNEAPOLIS, MN 55427
Exhibit A
(See following page)
10.00'10.00'10.00'10.00'20.00'10.00'10.00'10.00'10.00'40.00'30.00'30.00'20.00'20.00'10.00'10.00'20.00'30.00'30.00'30.00'10.69'30.00'20.00'20.00'20.00'25.00'10.00'20.00'20.00'20.00'20.00'20.00'20.00'20.00'25.00'10.00'10.00'10.00'25.00'10.00'20.00'10.00'10.00'10.00'20.00'100.00'60.00'50.00'25.00'30.00'30.00'30.00'10.00'10.00'10.00'30.00'10.00'10.00'10.00'10.00'10.00'20.00'20.00'20.00'10.00'20.00'80.00'30.00'30.00'10.00'30.00'30.00'30.00'30.00'30.00'10.00'30.00'10.00'10.00'20.00'
20.00'20.00'20.00'50.00'30.00'10.00'15.00'15.00'15.00'30.00'25.00'15.00'50.00'30.00'20.00'20.00'20.00'45.00'20.00'10.00'10.00'LANDSCAPE ARCHITECTURE SITE PLANNING CIVIL ENGINEERINGANDERSON - JOHNSONASSOCIATES,INC.7575 GOLDEN VALLEY ROAD SUITE 200 MINNEAPOLIS. MN 55427FAX (763) 544-0531 PH (763) 544-7129DateRegistration NumberCheckDrawnDate:CommI hereby certify that this plan, specification or report was prepared byme or under my direct supervision and that I am a duly Licensedunder the laws of the State ofRevisionsDescription Date NumScale:North7500 Olson Memorial Highway, Suite 300Golden Valley, MN 55427wenck.com | 952 837 3308ROSEMOUNT HIGHSCHOOL 2018ADDITION &PARKING3335 142ND STREET WESTROSEMOUNT, MINNESOTA 550683455 153RD STREET WESTROSEMOUNT, MINNESOTA 55068ISD #196: ROSEMOUNT -APPLE VALLEY - EAGANPUBLIC SCHOOLSPROFESSIONAL ENGINEERMINNESOTAC0.141" = 100'DARMET05/18/20181523174018010/27/2017DAVID A. REYEXHIBIT DAGREEMENTMAINTENANCEUGS 2UGS 3UGS 1STONE INV. = 934.40PIPE INV. = 934.90HWL = 944.74STORAGE = 6,349 SFSTONE INV. = 969.00PIPE INV. = 969.50HWL = 975.83STORAGE = 29,181 CFSTONE INV. = 929.50PIPE INV. = 930.00HWL = 933.48STORAGE = 80,778 CFLEGENDDRAINAGE AND UTILITY EASEMENT
Exhibit B
Maintenance Schedule and Routine Maintenance Item
Stormwater System Maintenance
The following guidelines shall be used to maintain the Stormwater Management Areas (Underground Storage
Systems and Sediment Control Structures).
Establish a routine maintenance schedule. It is suggested that maintenance occur in the spring (after snow
melt) and fall (following leaf drop). Maintenance should occur after an extended dry period when minimal water
is present in the systems. The maintenance schedule can be adjusted based on actual observed site
conditions.
Rosemount Elementary School - UGS 1
Spring Maintenance (following snow melt and accumulation of sand and grits from the winter months)
1. Access the tank system through one of the riser assemblies on top of the tank.
2. Vacuum accumulated silt, trash, sand, or other soil deposits from the bottom of the tank.
3. If direct access is required, follow local and OSHA rules for confined space entries.
4. Refer to Hyrdroworks Hydroguard Operations & Maintenance Manual (attached) for Sediment Control
Structure maintenance.
Early Summer Maintenance (early to mid June)
1. Access the tank system through one of the riser assemblies on top of the tank.
2. If sediment has accumulated, follow Spring Maintenance procedures as described above.
End of Season Maintenance (following leaf drop)
1. Collect leaves from lawn areas.
2. Access the tank system through one of the riser assemblies on top of the tank.
3. Vacuum accumulated silt, trash, sand, or other soil deposits from the bottom of the tank.
4. If direct access is required, follow local and OSHA rules for confined space entries.
5. Refer to Hyrdroworks Hydroguard Operations & Maintenance Manual (attached) for Sediment Control
Structure maintenance.
Rosemount High School - UGS 2
Spring Maintenance (following snow melt and accumulation of sand and grits from the winter months)
1. Access the tank system through one of the riser assemblies on top of the tank.
2. Using a manufacturer recommended culvert cleaning nozzle, jet the cleaning row wiht the JetVac
process. Vacuum accumulated sediments from the bottom of the tank system.
3. If direct access is required, follow local and OSHA rules for confined space entries.
Early Summer Maintenance (early to mid June)
1. Access the tank system through one of the riser assemblies on top of the tank.
2. If sediment has accumulated, follow Spring Maintenance procedures as described above.
End of Season Maintenance (following leaf drop)
1. Collect leaves from lawn areas.
2. Access the tank system through one of the riser assemblies on top of the tank.
3. Using a manufacturer recommended culvert cleaning nozzle, jet the cleaning row wiht the JetVac
process. Vacuum accumulated sediments from the bottom of the tank system.
4. If direct access is required, follow local and OSHA rules for confined space entries.
Rosemount High School - UGS 3
Spring Maintenance (following snow melt and accumulation of sand and grits from the winter months)
1. Access the tank system through one of the riser assemblies on top of the tank.
2. Vacuum accumulated silt, trash, sand, or other soil deposits from the bottom of the tank.
3. If direct access is required, follow local and OSHA rules for confined space entries.
4. Refer to Hyrdroworks Hydroguard Operations & Maintenance Manual (attached) for Sediment Control
Structure maintenance.
Early Summer Maintenance (early to mid June)
1. Access the tank system through one of the riser assemblies on top of the tank.
2. If sediment has accumulated, follow Spring Maintenance procedures as described above.
End of Season Maintenance (following leaf drop)
1. Collect leaves from lawn areas.
2. Access the tank system through one of the riser assemblies on top of the tank.
3. Vacuum accumulated silt, trash, sand, or other soil deposits from the bottom of the tank.
4. If direct access is required, follow local and OSHA rules for confined space entries.
5. Refer to Hyrdroworks Hydroguard Operations & Maintenance Manual (attached) for Sediment Control
Structure maintenance.
Hydroworks® Hydroguard
Operations & Maintenance Manual
Version 1.5
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Introduction
The Hydroguard is a state of the art hydrodynamic separator. Hydrodynamic separators
remove solids, debris and lighter than water (oil, trash, floating debris) pollutants from
stormwater. Hydrodynamic separators and other water quality measures are mandated
by regulatory agencies (Town/City, State, Federal Government) to protect storm water
quality from pollution generated by urban development (traffic, people) as part of new
development permitting requirements.
As storm water treatment structures fill up with pollutants they become less and less
effective in removing new pollution. Therefore it is important that storm water treatment
structures be maintained on a regular basis to ensure that they are operating at optimum
performance. The Hydroguard is no different in this regard and this manual has been
assembled to provide the owner/operator with the necessary information to inspect and
coordinate maintenance of their Hydroguard.
Hydroworks® HG Operation
The Hydroworks HG separator is unique since it treats both high and low flows in one
device, but maintains separate flow paths for low and high flows. Accordingly, high flows
do not scour out the fines that are settled in the low flow path since they are treated in a
separate area of the device as shown in Figure 1.
The HG separator consists of three chambers:
1. an inner chamber that treats low or normal flows
2. a middle chamber that treats high flows
3. an outlet chamber where water is discharged to the downstream storm system
Under normal or low flows, water enters the middle chamber and is conveyed into the
inner chamber by momentum. Since the inner chamber is offset to one side of the
structure the water strikes the wall of the inner chamber at a tangent creating a vortex
within the inner chamber. The vortex motion forces solids and floatables to the middle of
the inner chamber. The water spirals down the inner chamber to the outlet of the inner
chamber which is located below the inlet of the inner chamber and adjacent to the wall of
the structure but above the floor of the structure. Floatables are trapped since the outlet
of the inner chamber is submerged. The design maximizes the retention of settled solids
since solids are forced to the center of the inner chamber by the vortex motion of water
while the outlet of the inner chamber draws water from the wall of the inner chamber.
The water leaving the inner chamber continues into the middle chamber, again at a
tangent to the wall of the structure. The water is then conveyed through an outlet baffle
wall (high and low baffle). This enhances the collection of any floatables or solids not
removed by the inner chamber. Water flowing through the baffles then enters the outlet
chamber and is discharged into the downstream storm drain.
-2-
Figure 1. Hydroworks HG Operation – Plan View
During high flows, the flow rate entering the inner chamber is restricted by the size of the
inlet opening to the inner chamber. This restriction of flow rate into the inner chamber
prevents scour and re-suspension of solids from the inner chamber during periods of
high flow. This is important since fines, which are typically considered highly polluted,
are conveyed during low/normal flows.
The excess flow is conveyed directly into the middle chamber where it receives
treatment for floatables and solids via the baffle system. This treatment of the higher flow
rates is important since trash and heavier solids are typically conveyed during periods of
higher flow rates. The Hydroworks HG separator is revolutionary since it incorporates
low and high flow treatment in one device while maintaining separate low and high flow
paths to prevent the scour and re-suspension of fines.
Figure 2 is a profile view of the HG separator showing the flow patterns for low and high
flows.
-3-
Figure 2. Hydroworks HG Operation – Profile View
The HG 4i is an inlet version of the HG 4 separator. There is a catch-basin grate on top
of the HG 4i. Water flows directly into the inner chamber of the HG 4i through the catch-
basin grate on top of the structure. The grate is oversized to allow maintenance of the
entire structure. A funnel that sits underneath the grate on the top cap of the concrete
itself directs the water into the inner chamber during normal flows and the middle
chamber during high flows. Figures 3 and 4 show the flow paths for the HG 4i separator.
The inlet funnel is sloped towards the corner inlet and hence the wall of the inner
chamber. Water moves in a circular direction in the inner chamber since water enters
tangentially along the wall of the inner chamber due to the sloping funnel.
Water continues moving in a circular motion (vortex) through the rest of the structure
(through the middle chamber and baffle wall) until it is discharged from the separator.
-4-
During periods of peak flow the water will
back up from the corner inlet and overflow
into two side overflow troughs which
discharge directly into the middle chamber.
These overflow troughs are covered from
the surface such that water cannot directly
fall through them (i.e. water must back up
to enter the overflow troughs).
Accordingly this funnel provides the same
separate flow paths for low and high flow
as the other Hydroguard separators.
The whole funnel is removed for inspection
and cleaning providing.
Figure 3. Hydroworks HG 4i Normal Flow Path
Figure 4. Hydroworks HG 4i Peak Flow Path
-5-
Inspection
Procedure
Although all parts of the Hydroguard should be inspected, inspection and maintenance
should focus on the inner and middle chambers since this is where the pollutants
(floatable and sinking) will accumulate.
Floatables
A visual inspection can be conducted for floatables by removing the covers and looking
down into the separator. Multiple covers are provided on Hydroworks HG units to access
all areas of the separator (The HG 4 may have a single larger 32” (800mm) cover due to
the lack of space for multiple 24” (600mm) covers). Separators with an inlet grate (HG4i
or custom separator) will have a plastic funnel located under the grate or on the top cap
of the concrete that must be removed through the frame prior to inspection or
maintenance. If you are missing a funnel please contact Hydroworks at the numbers
provided at the end of this document.
TSS/Sediment
Inspection for TSS build-up can be conducted using a Sludge Judge®, Core Pro®,
AccuSludge® or equivalent sampling device that allows the measurement of the depth of
TSS/sediment in the unit. These devices typically have a ball valve at the bottom of the
tube that allows water and TSS to flow into the tube when lowering the tube into the unit.
Once the unit touches the bottom of the device, it is quickly pulled upward such that the
water and TSS in the tube forces the ball valve closed allowing the user to see a full core
of water/TSS in the unit. The unit should be inspected for TSS through each of the
access covers. Several readings (2 or 3) should be made at each access cover to
ensure that an accurate TSS depth measurement is recorded.
Frequency
Construction Period
The HG separator should be inspected every two weeks and after every large storm
(over 0.5” (12.5 mm) of rain) during the construction period.
Post-Construction Period
The Hydroworks HG separator should be inspected once per year for normal stabilized
sites (grassed or paved areas). If the unit is subject to oil spills or runoff from
unstabilized (storage piles, exposed soils) areas the HG separator should be inspected
more frequently (4 times per year). The initial annual inspection will indicate the required
future frequency of maintenance if the unit was maintained after the construction period.
-6-
Reporting
Reports should be prepared as part of each inspection and include the following
information:
1. Date of inspection
2. GPS coordinates of Hydroworks unit
3. Time since last rainfall
4. Date of last inspection
5. Installation deficiencies (missing parts, incorrect installation of parts)
6. Structural deficiencies (concrete cracks, broken parts)
7. Operational deficiencies (leaks, blockages)
8. Presence of oil sheen or depth of oil layer
9. Estimate of depth/volume of floatables (trash, leaves) captured
10. Sediment depth measured
11. Recommendations for any repairs and/or maintenance for the unit
12. Estimation of time before maintenance is required if not required at time of
inspection
A sample inspection checklist is provided at the end of this manual.
Maintenance
Procedure
The Hydroworks HG unit is typically maintained using a vacuum truck. There are
numerous companies that can maintain the HG separator. Maintenance with a vacuum
truck involves removing all of the water and sediment together. The water is then
separated from the sediment on the truck or at the disposal facility.
In instances where a vacuum truck is not available other maintenance methods (i.e.
clamshell bucket) can be used, but they will be less effective. If a clamshell bucket is
used the water must be decanted prior to cleaning since the sediment is under water
and typically fine in nature. Disposal of the water will depend on local requirements.
Disposal options for the decanted water may include:
1. Discharge into a nearby sanitary sewer manhole
2. Discharge into a nearby LID practice (grassed swale, bioretention)
3. Discharge through a filter bag into a downstream storm drain connection
The local municipality should be consulted for the allowable disposal options for both
water and sediments prior to any maintenance operation. Once the water is decanted
the sediment can be removed with the clamshell bucket.
Disposal of the contents of the separator depend on local requirements. Maintenance of
a Hydroworks HG unit will typically take 1 to 2 hours based on a vacuum truck and
longer for other cleaning methods (i.e. clamshell bucket).
-7-
Frequency
Construction Period
A HG separator can fill with construction sediment quickly during the construction period.
The Hydroguard must be maintained during the construction period when the depth of
TSS/sediment reaches 30” (750 mm). It must also be maintained during the construction
period if there is an appreciable depth of oil in the unit (more than a sheen) or if
floatables other than oil cover over 50% of the open water surface on the inlet side of the
outlet baffle wall.
The HG separator should be maintained at the end of the construction period, prior to
operation for the post-construction period.
Post-Construction Period
The Hydroguard was independently tested by Alden Research Laboratory in 2008. A
HG6 was tested for scour with initial sediment loads of 4.6 ft3 and 9.3 ft3. The results
from these tests were almost identical. Therefore, the 9.3 ft3 sediment load was used as
50% of the maximum sediment depth for maintenance in the calculation of the
maintenance interval for the HG6 separator based on the NJDEP maintenance equation.
Maintenance Interval (months) = 3.565 x (Sediment Storage) / (MTFR x TSS Removal)
Maintenance Interval (HG6) = 3.565 x 9.3 / (1.81x 0.60) = 30 months
All values (flow, sediment storage) can be scaled by the surface area making the
sediment depths and maintenance intervals equal for all separators.
The separator was loaded with the sediment in the inner chamber and middle chamber
with the majority of sediment (80%) located in the inner chamber. The inner chamber for
area represents approximately 44% of the separator surface area. The inner chamber is
4 ft (1200 mm) in diameter in the HG6. Therefore the 50% sediment depth for the HG6 in
the inner chamber would be:
9.3 ft3 x 0.80 / (3.14 x 4 ft2) x 12 in/ft = 7.1 inches (175 mm)
Accordingly the 100% sediment volume would represent 14.2” (350 mm) of sediment
depth in the inner chamber.
The HG separator must be maintained if there is an appreciable depth of oil in the unit
(more than a sheen) or if floatables other than oil cover over 50% of the open water
surface on the inlet side of the outlet baffle wall. It should also be maintained once the
accumulated TSS/sediment depths are greater than 14” (350 mm) in the inner chamber.
For typical stabilized post-construction sites (parking lots, streets) it is anticipated that
maintenance will be required annually or once every two years. More frequent or less
frequent maintenance will be required depending on individual site conditions (traffic
use, stabilization, storage piles, etc.). The long term maintenance frequency can be
established based on the maintenance requirements during the first several years of
operation if site conditions do not change.
Please call Hydroworks at 888-290-7900 or email us at support@hydroworks.com if you have
any questions regarding the Inspection Checklist. Please fax a copy of the completed checklist
to Hydroworks at 888-783-7271 for our records.
HYDROGUARD INSPECTION SHEET
Date
Date of Last Inspection
Site
City
State
Owner
GPS Coordinates
Date of last rainfall
Site Characteristics Yes No
Soil erosion evident
Exposed material storage on site
Large exposure to leaf litter (lots of trees)
High traffic (vehicle) area
Hydroguard Yes No
Incorrect access orientation ***
Obstructions in the inlet or outlet *
Missing internal components **
Improperly installed internal components **
Improperly installed inlet or outlet pipes ***
Internal component damage (cracked, broken, loose pieces) **
Floating debris in the separator (oil, leaves, trash)
Large debris visible in the separator *
Concrete cracks/deficiencies ***
Exposed rebar **
Water seepage (water level not at outlet pipe invert) ***
Water level depth below outlet pipe invert “
Routine Measurements
Floating debris depth < 0.5” (13mm) >0.5” 13mm) *
Floating debris coverage < 25% of surface area > 25% surface area *
Sludge depth < 14” (350mm) > 14” (350mm) *
* Maintenance required
** Repairs required
*** Further investigation is required
-1-
Other Comments:
Hydroworks® Hydroguard
One Year Limited Warranty
Hydroworks, LLC warrants, to the purchaser and subsequent owner(s) during the warranty period subject to the terms
and conditions hereof, the Hydroworks Hydroguard to be free from defects in material and workmanship under normal
use and service, when properly installed, used, inspected and maintained in accordance with Hydroworks written
instructions, for the period of the warranty. The standard warranty period is 1 year.
The warranty period begins once the separator has been manufactured and is available for delivery. Any components
determined to be defective, either by failure or by inspection, in material and workmanship will be repaired, replaced or
remanufactured at Hydroworks’ option provided, however, that by doing so Hydroworks, LLC will not be obligated to
replace an entire insert or concrete section, or the complete unit. This warranty does not cover shipping charges,
damages, labor, any costs incurred to obtain access to the unit, any costs to repair/replace any surface
treatment/cover after repair/replacement, or other charges that may occur due to product failure, repair or replacement.
This warranty does not apply to any material that has been disassembled or modified without prior approval of
Hydroworks, LLC, that has been subjected to misuse, misapplication, neglect, alteration, accident or act of God, or that
has not been installed, inspected, operated or maintained in accordance with Hydroworks, LLC instructions and is in
lieu of all other warranties expressed or implied. Hydroworks, LLC does not authorize any representative or other
person to expand or otherwise modify this limited warranty.
The owner shall provide Hydroworks, LLC with written notice of any alleged defect in material or workmanship
including a detailed description of the alleged defect upon discovery of the defect. Hydroworks, LLC should be
contacted at 136 Central Ave., Clark, NJ 07066 or any other address as supplied by Hydroworks, LLC. (888-290-
7900).
This limited warranty is exclusive. There are no other warranties, express or implied, or merchantability or fitness for a
particular purpose and none shall be created whether under the uniform commercial code, custom or usage in the
industry or the course of dealings between the parties. Hydroworks, LLC will replace any goods that are defective
under this warranty as the sole and exclusive remedy for breach of this warranty.
Subject to the foregoing, all conditions, warranties, terms, undertakings or liabilities (including liability as to
negligence), expressed or implied, and howsoever arising, as to the condition, suitability, fitness, safety, or title to the
Hydroworks Hydroguard are hereby negated and excluded and Hydroworks, LLC gives and makes no such
representation, warranty or undertaking except as expressly set forth herein. Under no circumstances shall
Hydroworks, LLC be liable to the Purchaser or to any third party for product liability claims; claims arising from the
design, shipment, or installation of the Hydroguard, or the cost of other goods or services related to the purchase and
installation of the Hydroguard. For this Limited Warranty to apply, the Hydroguard must be installed in accordance with
all site conditions required by state and local codes; all othe r applicable laws; and Hydroworks’ written installation
instructions.
Hydroworks, LLC expressly disclaims liability for special, consequential or incidental damages (even if it has been
advised of the possibility of the same) or breach of expressed or implied warranty. Hydroworks, LLC shall not be liable
for penalties or liquidated damages, including loss of production and profits; labor and materials; overhead costs; or
other loss or expense incurred by the purchaser or any third party. Specifically excluded from limited warranty
coverage are damages to the Hydroguard arising from ordinary wear and tear; alteration, accident, misuse, abuse or
neglect; improper maintenance, failure of the product due to improper installation of the concrete sections or improper
sizing; or any other event not caused by Hydroworks, LLC. This limited warranty represents Hydroworks’ sole liability
to the purchaser for claims related to the Hydroguard, whether the claim is based upon contract, tort, or other legal
basis.
Exhibit C
Legal Descriptions
PER BOOK 276 PAGE 112
Part of Lot 6, Auditor’s Subdivision No. 1, Rosemount, being more fully described as follow: Beginning at
a point 708 feet North and 1328.3 feet East of the Southwest corner of the Northwest Quarter of
Section 29, Township 115 North, Range 19 West; thence West 158.7 feet; thence North and parallel with
the center line of said Section 29, a distance of 1846.9 feet to a point 84.75 feet South and 1468.7 feet
West of the North quarter corner of said Section 29, thence East and parallel with the North line of said
Section 29, a distance of 855 feet; thence South and parallel with the aforesaid North and South center
line of said Section 29, a distance of 540 feet; thence East 266.7 feet to the center of State Trunk
Highway No. 218; thence Southeasterly along the center line of said Highway 647 feet to the North line
of the school property extended to the center line of said Highway; thence West along the North line of
school property 991.18 feet to the Northwest corner of school property (being the Northwest corner of
that property described in Book 239 of Deeds, Page 351, in the office of the Register of Deeds in and for
Dakota County, Minnesota); thence South and along the West line of said school property 668 feet to
the point of beginning. Except commencing at a point on the West line of State Truck Highway No. 218,
which point is 400 feet due North of the North line of Murphy Street in the Village of Rosemount; thence
West 100 feet; thence North 160 feet; thence East to the West line of said State Trunk Highway No. 218;
thence Southerly along the West line to the place of beginning. Containing 28.28 acres more or less
exclusive of highway right of way.
AND
PER DOC. NO. 377326 FINAL CERTIFICATE #70605
All that part of Lot Six (6) Auditor’s Subdivision No. One (1), Rosemount, Dakota County, Minnesota,
described as follows, to-wit; commencing at a point on the West line of State Trunk Highway No. 218 as
now established, 400 feet North of the North line of Murphy Street, thence West 100 feet, thence North
160 feet, thence East to the West line of said Highway No. 218, thence Southerly to the point of
beginning, according to the plat thereof now on file and of record in the office of the Register of Deeds
within and for said County and State.
AND
PER BOOK 287 PAGE 83
All that part of Lot 6 in Auditor’s Subdivision No. 1 to the Village of Rosemount, Dakota County,
Minnesota, described as follows: Commencing at a point 24.75 feet South from the Northwest corner of
the Northwest Quarter(NW ¼) of Section 29, Township 115, Range 19, running thence South 1294 feet;
thence East 165 feet, thence South 1318.75 feet, thence East 1171.67 feet, thence North 946 feet,
thence East 571.25 feet, more or less, to the SW corner of the School Lot, thence running North along
the West line of said School Lot 400 feet; thence East along the North line of said School Lot 384.55 feet,
to the West line of the Dodd Road, thence northerly along the west line of said Dodd road to a point
24.75 feet South of the North Line of said Northwest Quarter (NW1/4) of said Section 29, thence West
2427.8 feet to the place of beginning; EXCEPTING THEREFROM, HOWEVER, those certain tracts
described in the following described documents on file in the office of the Register of Deeds of Dakota
County, Minnesota; 213 of Deeds, page 229, 213 of Deeds, page 554, 239 of Deeds, page 351, 239 of
Deeds, page 352, 239 of Deeds, page 598, 245 of Deeds, page 112, 249 of Deeds, page 24, 276 of Deeds,
page 112, 255 of Deeds, page 367, 255 of Deeds, page 368, 255 of Deeds, page 401, 255 of Deeds, page
402, 269 of Deeds, page 254, 271 of Deeds, page 39, 271 of Deeds, at page 153, 271 of Deeds, page 487,
276 of Deeds, page 112; AND ALSO EXCEPTING THEREFROM, the South 540 feet of the North 600 feet of
the East 235 feet of said tract; according to the plat of said Auditor’s Subdivision No. 1 now on file and of
record in the office of the Register of Deeds within and for said County and State.
AND
PER 294 PAGE 466
The South 540 feet of the North 600 feet of the East 235 feet of Lot Six (6) in Auditor’s Subdivision No. 1
to the Village of Rosemout, Dakota County, Minnesota, according to the plat thereof now on file and of
record in the office of the Register of Deeds within and for said county and state.
AND
PER UNRECORDED DEED DATED MARCH 17, 1982
That part of the South Half of the Southwest Quarter of Section 20, Township 115, Range 19, Dakota
County, Minnesota described as follows: Commencing at the southwest corner of said South Half of the
Southwest quarter; thence North 2 degrees 54 minutes 02 seconds West (assumed bearing) along the
west line thereof a distance of 24.75 feet; thence North 88 degrees 14 minutes 18 seconds East, parallel
with the south line of said South Half of the Southwest Quarter a distance of 1027.13 feet to the point of
beginning of the land to be described; thence North 1 degree 45 minutes 42 seconds West a distance of
775.50 feet; thence North 88 degrees 14 minutes 18 seconds East, parallel with said south line a
distance of 850.00 feet; thence South 1 degree 45 minutes 42 seconds East a distance of 775.50 feet;
thence South 88 degrees 14 minutes 18 seconds West, parallel with said South line a distance of 850.00
feet to the point of beginning. Containing 15.13 acres.
AND
PER WARRANTY DEED RECORD NO. 151 PAGE 447
Commencing at a point of the westerly line of Dodd Road; the following described courses from the
center of section Twenty Nine (29), Township One Hundred and Fifteen (115), Range Nineteen (19), 446
feet North on North and South Quarter line and 614.30 feet on an angle of 19 degrees 30 minutes
turned west from said quarter line and 34.78 feet west, this point being the place of beginning to
describe the following tract of land; thence west and parallel with the quarter line 131.72 feet; thence
South and parallel with the quarter line 55 feet; thence west and parallel with the quarter line 374.70
feet, thence North and parallel with the quarter line 400 feet; thence east and parallel with the quarter
line 384.35 feet to the westerly line of said Road; thence Southeasterly along the westerly line of said
road 363.03 feet to the place of beginning. Containing four (4) acres of land.
AND
PER BOOK OF DEEDS 213 PAGE 554
Part of Lot Six (6) of Auditor’s Subdivision No. 1, Rosemount, described as follows, to-wit: Commencing
at a point which is 374.70 feet west of the southwest corner of Lot Twenty-Seven (27) of said Auditor’s
Subdivision No. 1, Rosemount, which point of beginning is also the southwest corner of lot now owned
by School District No. 19, thence running north along the west line of said school lot 400 feet, thence
West 326.7 feet, thence south 400 feet, thence east 326.7 feet to the place of beginning, containing 3
acres, more or less, according to the plat thereof now on file and of record in the office of the Register
of Deeds within and for said Dakota County, Minnesota.
AND
PER BOOK 239 OF DEEDS, PAGE 348 (RECITED FROM 2689934)
Part of Lot numbered six (6), Auditor’s Subdivision Number One (1), in the village of Rosemount,
described as follows, to-wit: Commencing at a point one thousand three hundred thirty six feet and
67/100 (1336.67) feet east and two hundred thirty six (236) feet north of the southwest corner of the
northwest quarter (SW cor of NW ¼) of section numbered twenty nine (29), Township one hundred
fifteen (115) Range nineteen (19), thence running east eighty five (85) feet, thence south thirty three
(33) feet, thence east two hundred twenty two and 5/10 (222.5) feet, thence south twenty (20) feet,
thence East eighty (80) feet, thence north seven hundred sixty three (763) feet, thence west three
hundred eighty five (385) feet, thence south seven hundred ten (710) feet to the place of beginning,
containing six and fifty three one hundredths (6.53) acres of land, more or less.
EXCEPT
PER BOOK 238 OF DEEDS, PAGE 637
Part of Lot six (6), Auditor’s Subdivision No. one (1) Rosemount, described as follows: Commencing at a
point sixty (60) feet west and two hundred three (203) feet north of the southwest corner of Lot eight
(8) in said Auditor’s Subdivision No. one (1), thence north one hundred twelve (112) feet, thence east
three hundred eighty five and sixty three hundredths (385.63) feet, to the West end of John Street, as
now located, thence north sixty (60) feet, thence west four hundred fourteen and sixty three
hundredths (414.63) feet, thence south two hundred twenty five (225) feet, thence East eight and thirty
seven hundredths (8.37) feet, thence north fifty three (53) feet, thence East twenty and sixty three
hundredths (20.63) feet to the point of beginning.
ALSO EXCEPT
PER BOOK 191 OF DEEDS, PAGE 531
All that part of Lot six (6), Auditor’s Subdivision Number One (1), Rosemount, described as follows:
Beginning at a point on the north line of John Street, which point is one thousand three hundred twenty
eight and 30/100 ths (1328.30) feet East and four hundred eight (408) feet North of the southwest
corner of the northwest quarter (NW ¼) of Section 29, Township 115, Range 19, thence North from said
point of beginning three hundred (300) feet, thence east twenty nine (29) feet, thence South three
hundred (300) feet, thence West twenty nine (29) feet to the point of beginning, all according to the plat
thereof now on file and of record in the office of the register of deeds in and for said County and State.
The above described land to be used by said Village of Rosemount for street purposes.
ALSO EXCEPT
PER QUIT CLAIM DEED DOCUMENT NUMBER 2519177
All of Lot Ten (10), and that part of Lot Six (6), described as follows;
Beginning at the Northeast corner of Lot Ten (10), thence North 20 feet along an extension of the East
line of Lot 10, thence West 55 feet along a line parallel to and 20 feet North of the North line of Lot 10,
thence South 20 feet along the extension of the West line to the Northwest corner of Lot 10, thence East
along the North line of Lot 10 to the point of Beginning, all in Auditor’s Subdivision 1, Village of
Rosemount, according to the recorded plat thereof, Dakota County Minnesota.
ALSO EXCEPT (RECITED FROM 2689934)
That part of Lot six (6), Auditor’s Subdivision No. 1, Rosemount, described as follows. Commencing at
the Northwest (NW) corner of Lot Eleven (11), in said Auditor’s Subdivision No. 1, Rosemount; thence
North Twenty (20) feet; thence East Fifty and Sixty-three hundredths (50.63) feet, thence South Twenty
(20) feet; thence West along the North line of said Lot Eleven (11) Fifty and Sixty-three hundredths
(50.63) feet, to the place of beginning, according to the plat thereof now on file and of record in the
office of the Register of Deeds within and for said County and State.
AND
PER BOOK OF DEEDS 255 PAGE 368
All that part of Lot six (6) Auditor’s Subdivision No. one (1) Rosemount, described as follows:
Commencing one thousand three hundred thirty six and sixty seven hundredths (1336.67) feet East and
one hundred eighty three (183) feet north of the southwest corner of the Northwest quarter (NW ¼) of
Section twenty nine (29), Township one hundred fifteen (115), Range nineteen (19) West, thence north
and parallel to the East line of said northwest quarter (NW ¼) seven hundred sixty three (763) feet,
thence east two hundred thirty eight and sixty five hundredths (238.65) feet, thence North four hundred
thirty (430) feet to the northwest corner of the present school property, thence west two hundred forty
seven and two hundredths (247.02) feet, thence south eleven hundred ninety three (1193) feet to the
northwest corner of the present Carl A. Rechtzigel property, thence east eight and thirty seven
hundredths (8.37) feet to the place of beginning, containing two and fifty eight hundredths (2.58) acres
of land.
AND
PER BOOK OF DEEDS 255 PAGE 367
All that part of Lot Six (6), Auditor’s Subdivision No. One (1), Rosemount, described as follows:
Commencing one thousand three hundred thirty-six and sixty-seven hundredths (1336.67) feet East and
One hundred eighty-three (183) feet North of the Southwest corner of the Northwest quarter (NW ¼) of
Section Twenty-nine (29), Township One hundred fifteen (115), Range Nineteen (19) West, thence North
and parallel to the East line of said Northwest quarter (NW ¼) seven hundred sixty-three (763) feet,
thence East Two hundred thirty-eight and sixty-five hundredths (238.65) feet to a point of beginning;
thence from said point of beginning North thirty (30) feet, thence East One hundred forty eight and
eighty-five hundredths (148.85) feet, thence South thirty (30) feet, thence West One hundred forty-
eight and eighty-five hundredths (148.85) feet to the point of beginning containing .125 acres of land.
AND
PER BOOK OF DEEDS 242 PAGE 264
Part of Lot numbered six (6) Auditor’s Subdivision No. one (1) in the Village of Rosemount, further
described as follows; Commencing at the northeast corner of Lot numbered nine (9) in said Auditor’s
Subdivision No. one (1), thence East one hundred five and sixty three hundredths (105.63) feet, thence
north one hundred sixty five (165) feet, thence West twenty seven and one half (27 ½) feet, thence
south one hundred forty five (145) feet, thence West seventy eight and thirteen hundredths (78.13)
feet, thence south twenty (20) feet to the point of beginning.
AND
PER BOOK OF DEEDS 255 PAGE 238
Part of Lot numbered Six (6), Auditor’s Subdivision Number One (1) in the Village of Rosemount,
described as follows: Commencing at a point One Thousand Three Hundred Thirty-six and sixty-seven
hundredths (1336.67) feet East and Two Hundred Three (203) feet North of the Southwest corner of the
Northwest Quarter (SW corner of NW ¼), of Section numbered twenty-nine (29), Township one hundred
fifteen (115), Range nineteen (19), thence running east eighty-five (85) feet, thence north Thirty-three
(33) feet, thence west eighty-five (85) feet, thence South thirty-three (33) feet to the point of beginning.