Transcript Effects of golf course construction and operation on water

Effects of golf course construction and
operation on water chemistry of headwater
streams on the Precambrian Shield
Jennifer G. Winter
Peter J. Dillon
May, 2004
Presented by:
Mark Williams
David Millar
Purpose:
To investigate the effects of golf course
construction and operation on the water
chemistry of Precambrian Shield streams.
(Canada)
Summary
• Streams were more alkaline post golf course
construction
• Concentrations of base cations and nitrates increased
downstream of operational golf courses
• Total phosphorous in the streams increased
• Vegetation acting as a buffer for these substances
appears to drastically reduce their concentrations if
implemented near golf courses.
Background
• Soils on the Shield are acidic, dolomite and limestone
are commonly added to “up” the pH.
• Golf course’s require that the land loose much of it’s
natural ability to absorb nutrients (via deforestation),
natural sinks of nitrogen and phosphorous removed
• Runoff from golf courses poses a threat to water quality,
as fairways, greens, and other “manicured” areas are
meant to drain. (Gravel and sand is usually the
foundation for topsoil, hydraulic conductivity
Site Description
• Seven golf courses were
sampled (A-G)
• Stream locations unknown, as
to protect golf course identity,
but in vicinity of the District of
Muskoka
• Surface geology is primarily till
deposits, generally <1m thick
• Podzolic, brunisolic soils
• Courses A-E in operation from
5-10, >50 years
• Course F in operation since
summer, 2001
Samples were collected
upstream of courses A, D and
E for upstream versus
downstream comparisons.
Three inflowing streams
converged on course D.
Comparisons were also made
with data from 18 reference
streams in undeveloped areas
(watershed area > 80% forest
and wetland).
Fertilizer Application Rates for Each Course
Stream sites F1 – F4 showed the highest rates of Phosphorous applications
25-50 kg/ha/year, at course F
Fertilizer Application
• Courses used a combination of organic or controlled and slow
release nitrogen fertilizers in their applications
• Course F commonly uses treated sewage effluent for irrigation,
which is more than likely linked to the increase in P concentrations
at the stream sampling stations.
• Courses F and G also linked to higher N and K concentrations in the
adjacent stream
Water Chemistry
• “Grab” samples taken monthly throughout the year
• Cations, anions, total phosphorus and nitrogen species were
measured weekly on courses B, C and F, and on D until 2001.
• Alkalinity was measured via Gran titration, pH by glass electrode,
conductivity by conductivity meter, and concentrations of calcium,
sodium, potassium and chloride by ion chromatography.
• Nitrate, total Kjeldahl nitrogen and total phosphorus were measured
colorimetrically using an autoanalyzer. Total nitrogen concentration
was calculated by adding the total nitrate (nitrate + nitrite) and total
Kjeldahl nitrogen concentrations together
• Total P,K, nitrate, and Kjedahl N also measured in inflows/outflows of
ponds adjacent to courses B,C and D
Results
• Sites F3, F4 drained a larger area of Course F
than F1 and F2
• Increase shown in alkalinity, conductivity,
sodium, chloride, calcium and potassium when
construction of the course began in 1999
• Total P concentrations higher in both streams
after course remodeling and rootzone (fertilizer)
application
Alkalinity, Na, Conductivity, Chloride
monthly measurements for Stream F
Ca, NO3, P, and Total P concentrations in stream
from course F
Total P concentration for
stream/course F
• P concentrations
peaked during the
summer months (~80
μg/L) and in the early
fall in preparation for
winter (~60 μg/L)
Alkalinity, Na, Conductivity, and
Chloride for stream/course G
Ca, Nitrate, K, Total P for
stream/course G
Course G
• Alkalinity increased in station G1 over sampling
period, >100 μeqv/L
• “Mean concentrations of potassium and total
phosphorus were three-fold and two-fold higher,
respectively, in G1 in the summer of 2001 than
in the summer of 2000, while nitrate
concentrations were higher in the summer of
2000 (24% increase) and 2001 (43% increase)
than in 1999”
Stream C showed the highest total P concentrations in the
1999-2000 season as well as the 2000-2001 season
Note: no upstream sites were measured for these courses
therefore an additional N,P,K source is possible
Stream A showed a decrease in total P past the course, yet showed a dramatic
increase in nitrate concentration downstream.
Courses D and E show similar results
Relationships between stream
concentrations and physical variables
• Various sinks for nutrients, such as
vegetative covering along the streams, as
well as soil type etc.. can (and do) affect
stream concentrations.
• Golf course variables such as playable
area (fairway size), soil composition, and
drainage pathways can also affect these
results.
Redundancy analysis (RDA) diagram showing sample
scores from the ordination of 2000–2001 hydrologic year
(Mean water chemistry of streams)
RBQI: River Bank Quality Index
• Measures the ability
for a river to
contribute to it’s own
water quality, which is
based on various
ecological and
geological controls.
• Calculated by the
formula:
ai: the area covered by
the vegetation class (i.e.
forest, wetland etc., m2
Pi: a standardized
weighting factor for each
class of ai
D: total area surveyed
(m^2)
Mean 2000/01 nutrient concentrations vs.
RBQI scores
•
“The mean 2000–2001 hydrologic
year concentrations of total
nitrogen and total phosphorus
were significantly related to the
total area of unmanaged
vegetation in the 1800m^2
surrounding the sampling sites
and to the RBQI score.”
•
“Overall, the more the unmanaged
vegetation surrounding the stream
site, or the higher the RBQI score,
the lower the concentrations of
nutrients in the stream.”
(For all courses excluding D)
Conclusions
• Golf course operation clearly had (has) an effect
on water quality
• Generally, streams were more alkaline and
higher in concentrations of cations and nitrates
downstream of golf courses
• P and K concentrations are naturally low in
Boreal forests, so elevated P and K levels
indicate runoff and contamination from direct
fertilization of turfgrass
Conclusions
• “During construction through to operation, changes were
observed in water chemistry over time in those courses
that drained forested areas prior to construction.
• Alkalinity, conductivity and concentrations of total
phosphorus, nitrate, potassium and other ions increased
in these streams over the course of the study.
• The streams with minimal water chemistry changes
during and after construction were those that drained a
small proportion (<10%) of the golf course property (G2)
or were located close to pre-existing residential
development (F2).”
Conclusions
• Drainage morphology and subsurface
conditions play a vital role in how nutrients
are leeched into groundwater and above
ground streams
• The River Bank Quality Index is a good
indicator of how well ecological controls
effect nutrient cycling in drainage areas.
Recommendations
• To reduce nutrient levels in streams:
1.) fertilize as little as possible
2.) maximize the riparian zone between golf
courses and streams to act as a buffer
3.) maintain stream bank conditions (thus
maximizing the RBQI)