Core Monitoring Pla

Step-down Process for Evalua

Core Monitoring Components 

Downstream Water Quality P
Proposed Core Monitoring Plan for Downstre

30-miQ,T,C

87-mQ,T,

166-mileQ,T,C,SSC

226-mileQ,T,C,SSC

Kanab

Q,T,SSC

Havasu

Q,T,SSC
Step 1: AMWG Priority

Does the data directly or indirectly address an A

- Directly addresses AMW- Directly addresses AMW- Indirectly addresses AMW

Physical habitat

- Indirectly addresses AMW

Aeolian transport/arroy

- Indirectly addresses AMW

Flows affect sediment t

Priority 1: Why are the humpback chu

b n

ot thrivin

g, and what can w

e do 

about it? H

ow many H

BC are there 

and how are they doing?Priority 2: Which cultural resources, including T

CPs, are within the APE, 

which should we treat, and how do we best protect them? What are the status and trends of cultural resources and what are t

he agent

s of

deterioration?Priority 3: What is the best flow regime?Priority 4: What is the impact of sediment loss and what should w

e do 

about it?Priority 5: What will happen when we test or implement the TCD? How shoul

d it be operated? Are 

safeguards need for management?
Step 2: MOs and CMIN

Does the data directly or indirectly add

r

ess an existing M

MOs directly addressed

7.1

Attain water temperature ranges and seasonal variability i

necessary to maintain or attain desired levels of desirable 

7.2

Maintain water quality in the mainstem of the Colorado Riv

7.3

Maintain suitable water quality in Glen Canyon Dam relea

management objectives.

7.4

Maintain flow dynamics associated with power plant opera

maintenance flows.

8.1

Maintain or attain fine sediment abundance, grain-size, dis

channel below 5,000 cfs.

8.2

Maintain or attain fine sediment abundance, grain-size, dis

margins (not eddies) from 5,000 to 25,000 cfs.

8.3

Maintain or attain fine sediment abundance, grain-size, dis

below 5,000 cfs.

8.4

Maintain or attain fine sediment abundance, grain-size, dis

5,000 to 25,000 cfs.

8.5

Maintain or attain fine sediment abundance, grain-size, an

shorelines between 25,000 cfs and the uppermost effects releases.
CMINs addressed

1) Surface Water Measurements

7.4.1 Determine and track releases from Glen Canyon Dam unde

conditions.- Addressed directly through flow measurements at Lees F

7.4.2 Determine and track flow releases from Glen Canyon Dam

flow duration, upramp, and downramp conditions.- Addressed directly through flow measurements at Lees F
CMINs addressed

2) Sediment Transport Measureme

8.1.2 What are the monthly sand and silt/clay export volumes an

characteristics, by reach, as measured at Lees Ferry, LoweGrand Canyon, and Diamond Creek Stations?- Addressed directly through proposed monitoring at 61-mi

Nearly continuous monitoring is required to get monthly vo

- Do not propose sediment monitoring at Lees Ferry- Propose additional stations at 30-mile and 166-mile

8.1.3 Track, as appropriate, the monthly sand and silt/clay input 

characteristics, by reach, as measured or estimated at the Colorado River stations, other major tributaries like Kanab and “lesser” tributaries.- Addressed directly through proposed sampling on the Pa

mouth), Kanab and Havasu Creeks.

- No proposed monitoring on “lesser” tributaries; this is still 
CMINs addressed

3) Water Chemistry Measuremen

7.1.1 Determine the water temperature dynamics in the main cha

appropriate), backwaters, and near-shore areas throughouecosystem. - Addressed directly through temperature monitoring at -15

61-mile, 87-mile, 166-mile and 226-mile, Paria, LCR, Kan

- Backwaters and near-shore areas not proposed for Core 

assessing methodology and locations

7.1.2 Determine the seasonal and yearly trends in turbidity, wate

conductivity, DO, and pH, (decide below whether selenium the main channel throughout the Colorado River ecosystem- Water temperature and conductivity addressed directly at - Turbidity, DO, pH, and selenium not included. Assessing 

and pH data; may become part of CM based on foodbase 

7.1.3 What are the status and trends of water quality releases fro

- Addressed directly through monitoring (temperature and c

- Other parameters (e.g. nutrients, organics) awaiting resul
Step 3: Compliance

Does the data satisfy a specific legal compliance req

GCPA and the NPS Organic Act (e.g. EIS/ROD, ES

Only flows at Lees Ferry for Compact, I th

Step 4: Legacy

Does the data contribute to an historical record that is im

Lees Ferry flow since 1921; temperature since 1949 

Grand Canyon flow since 1922; temperature since 194

Sediment mass balance began in 199

Breaking the sediment records has more consequences 

temperature records. A break in the sediment records mea

balance from zero.
Step 5: Data quality/availab

Is the accur

acy and precision of the data known for prop

and if so, is the level of accuracy/precision adequate, ina

adequate to meet t

he needs of the program? How will da

Temperature: ±0.15°C

Conductivity: ±0.5% of reading

±10% for mainstream sediment loads

±20-30 for tributary sediment loads

-5.0-4.0-3.0-2.0-1.0

0.01.02.03.04.05.06.0

05,00010,00015,00020,00025,00030,00035,00040,00045,00050,000

MASS-BALANCE SAND BUD

GET

BET

WEEN LEES FERRY AND 

T

HE GRAND CANYON GA

GE

AUG 1999

NOV 1999

FEB 2000

MAY 2000

AUG 2000

NOV 2000

FEB 2001

MAY 2001

AUG 2001

NOV 2001

FEB 2002

MAY 2002

AUG 2002

NOV 2002

FEB 2003

MAY 2003

AUG 2003

NOV 2003

FEB 2004

MAY 2004

AUG 2004

NOV 2004

FEB 2005

MASS-BALANCE UNCERTAINTY ENVELOPE

WATER DISCHARGE

SAND MASS IN REACH RELATIVE TO

THAT ON AUG 15, 1999 (million metric tons)

DISCHARGE AT THE LEES FERRY GAGE (ft

3

/s)

CONTROLLED FLO

OD

ACCUMULATION

EROSION

EvenavailaGCM
Step 6: Cost/benefit and risk as

What are the r

elativ

e merits of collecting this data rel

collection?

Sediment and temperature are directly linked to habitat an

They are probably the WQ parameters most affected b

These parameters either directly or indirectly relate to the 

Step 7: Status of knowled

What is the current status of knowledge about the resou

intended to monitor?

Temperature: Colder and less variability than pre-dam; d

more downstream warming occurs

Sediment: MLFF operations during minimum release year

mass balance. High flows move sediment to high eleva

potentially at the expense of low elevation sand 
Step 8: Methodology

Does methodology exist t

hat provides acceptable accu

frequency of data?

Temperature data collection methodology is standardizeGCMRC has developed a unique system for providing thsediment data necessary to develop a continuous mass et al. paper) for the Colorado River in Grand Canyon, an location to do this. Whether the uncertainty bounds are the managers; it would be very costly to reduce them.

Budget

$1,104,000 –

Arizona WRD estimate to undertake 

$200,000 –

GCMRC salaries
Linkage to Modeling Effo

Monitoring data is essential for continued developme

models, as well as for boundary cond

Flow data 

→ UNSTEADY: LF, Paria, LCR data need

conditions. Other sites useful for periodic testing of tSediment data 

→ 1D/2D models under development 

Data essential for calibrating/validating models.Temperature data 

→ Upcoming development of main

backwater models. Data essential for calibrating/vali

Well established models can reduce the need for monalways need boundary conditions, and it’s wise to mainwithin system station for periodic checking of the mode